I don't think you're off-base on that RomanGuy.  It's hard to imagine a caravan creating food out of thin air.  Caravans increasing trade which would then increase gold -- that makes sense.

They produce food because the farmer driving it has to stop and shoot buffalo, even though he can only carry 200lbs of it back to his wagon.  Mary and Todd have cholera.

Not quite.... So you think its realistic that a wagon travelling from a city without a farm, arrives in a city with a farm, with fresh extra food in its cargo?
Then when it travels from the farm-city to the non-farm-city, it has nothing in its cargo.

Thats the problem, the caravans are essentially carrying food TO the food producing cities (hence the % bonus), if they carried food FROM the farms to the NON-food cities, the non-food cities would get a % bonus to slow their food consumption.

But as it is, farming cities get food from caravans, out of thin air. Its an extra % food that is being created, not a % food that is being saved by "shipping food to empty cities before it spoils".

Imo the caravans should provide a bonus to whatever the cities connected are producing the most.
If a gold-producing city sends a caravan to a metal-producing city, the metal city should get a slight 5-10% bonus to metal production, and the gold city should get a bonus to gold production.

It makes absolutely no sense to have a food bonus between non-farm cities. It just makes the caravans worthless.
AND another thing, since you CANT trade food via diplomacy (which i think you should be able to, like civ4's tradeing resource for resource (cancellable), there is even less point for the caravans. If they however provided a small materials/metal/gold bonus, a whole new gameplay aspect could open up, via setting up trade routes EVERYWHERE (and actually getting that extra trade route tech, ive never had to bother with it), including to the other ai faction's cities, and using the resources you gain from that in diplomacy or to fund your empire.

As it is now, trade is so unrealistic. Its just there to make food...... Trade has never been about making food in any other strategy game tbh

I think the logic behind caravans and food is that food is a perishable good.   A given city with a farm can produce a large amount, but it can only physically use so much of it, and a lot of it, theoretically, goes to waste.   Caravans that are linked from a non-producing city to a producing city make less of it go to waste by transporting it to places where it can be used before it goes bad.   This is represented by the output of the city increasing.  Perhaps the caravan operator gets a cut of gold for his services, but gold isn't conjured out of nothingness for our use.

That's still kind of an extremely roundabout and unintuitive way to do things.

I think caravans should provide a bonus to whatever resources the linked cities produce.   Not only would that make more intuitive sense; it'd make caravans important strategic targets.   In a war against the AI (or soon, another person!) you could send mobile, lightly armed, inexpensive raiding parties to disrupt the opponent's caravans and cripple their economy, kind of running interference while your main army does the marching and territory-taking.

In fact, I quite like that idea.

City 1 prodeces 5 tons of food, city 2 10 tons.  Somehow, adding a caravan between the two cities gives >15 tons of food.  Said extra food miraculously appears out of nowhere.

Unless the caravans contain mini-greenhouses that grow food while traveling, or they hunt buffalo like BLoads jokingly suggested, caravans should reduce total food supply -- that should be the price paid for a global pool.

FWIW... my two cents  

I think the current implementation is a design trade-off decision, I have no actually proof it's only my opinion or guess.  I based this off existing game mechanics of Food Production.  Unlike most strategy games were food is a required resource to expand one's population AND farms or other food producing improvements can be constructed, in Elemental only nodes that are fertile can produce food, one cannot just construct a farm on a patch of tilled dirt and add water.  Therefore Food has be greatly restricted (possibly intentionally by design to prevent early game population rushes and overbuilding of housing and markets? IDK) but there mid game and late game needed to be another source of food and there is not except for caravans.

So does it make Real World logical sense?  No it certainly does not, though neither does imbuing someone with magic.  I think the mechanics could have been better thought out and communicated.  I also think there is likely a better way but do not know what that is unless SD shares there design criteria for why they implemented food production via only two methods.  Farms and Caravans.  I think the two are very tightly coupled.  If caravans were changed to produce gold w/o another source to buy food with said gold my game economies would collapse. 

I think that variety is the true value of caravans. Regardless of what actual resource is being traded, the idea that you can get exotic foods and materials that allow you to do stuff you couldn't do before improves your life. This is why there is a bonus for traveling farther, because the farther you travel the more exotic your goods are.

So i think the current system makes sense (in terms of getting a net value thats greater than both cities production combined) but I don't see how this limits what resources a caravan could carry. Similarly this doesn't really force the developers to choose a particular method of food and resource generation amongst cities. I think caravans and resource production are 2 different issues as long as caravans aren't required to have prosperous cities.

Summary: I agree with OP and there is no reason why the Devs can't tweak the way resources work.

Don't worry, you're not the only one who gets it

Better ford that river.

there is sense in this. but, two small points

- there is also the first level spell, nature's bounty. this adds up when cast on every settlement

- the situation is nothing compared to the necessity of finding metal resources. metal cannot be had from any other source (except from diplomacy) and without it you CANNOT build a military.

Sethai,

Good point on nature's bounty I did overlook that source but unintentially so.  Does Nature's Bounty +1 food occur before or after the food bonus from Graneries and caravans?  I sort of think there are bugs that the Champ bonuses and enchantment bonuses are applied after and not before the cities % bonuses.  These are minor compared to others but i hope they are on the list to get squashed at some point.

I'm not quite sure how they worked during Beta 2 but I believe that caravans provided Gold and Materials when they reached their destination. Althought I never really understood how they worked, I know that since there was no limits on Caravans you could end up producing obcene amounts of gold and material per turn due to that mechanic.

While I hope they make trading a bit more interesting I also hope that they don't break caravans like that since they would go from "soso" to "omgbbqgood". There are many great ideas here lets hope the devs can use them in cool ways and give us a nice trading system!