The food system can be tough in the beginning.
The best start for the game is to abuse the merchant on the first island who restores your rations for free. Just grind some enemies around that island to get a small stock of money, 200 or 300 gold. As a nice side effect you'll also level up a bit. When you're rations are low, just get them restored for free.
In Chapter 1 you'll soon get a Merchant to your caravan, at that point all your food problems will be solved. Put him in front of a wagon and he'll get you 10 extra gold every battle. With that you'll soon be swimming in money.
The food system IS there for a good reason, it makes greater variety with the classes. You'll have to think more about who to take with you in the wagons. Without the food system, one would only stock up damage dealer after extra damage dealer, so the whole caravan system would boil down to increasing your bonus damage, that would be boring woulnd't it
Just stick to the game a bit, most people grow to like it very much after the first few hours, it gets much more interesting once you'll start recruiting more wagon members