Free: Contests & Raffles.
All of my hunting buddies laugh at how much chow I take with me. I generally have enough to get me well into the next day with out the tummy grumbles. With that said don't over think it. There is now reason to suffer while hunting especially if just plan to be gone for the day and the worst case scenario is you have to spend the night in the woods. Just load up on things that you would enjoy eating while hunting. Some healthy, some not so much. You will burn calories. If you get into a situation where you may have to pack a long distance. It helps to have something to put in your tummy when needed. Also food fuels the furnace and helps keep you warm. Again don't over think it.
Been a bunch of good things in the way of grab & go type snacks mentioned, really can't go too wrong there. Just pick stuff you like to munch on. One thing I learned from a buddy a long time ago that I do now is keep a one burner propane stove in my rig, and I stock up on a dozen or so different kinds of canned foods, like chili, stew, soups, etc. No worries about spoiling or getting messed up since they are in cans. Several have pop top lids so a can opener isn't needed, but good to have anyway along with a few pieces of metal silverware and a couple small cooking pots.All of this fits neatly into the medium sized Rubbermaid type containers, easy to grab it and toss in the rig.Used to do the sandwich and other "cold" finger foods only, but on a cold or wet day, getting back to the rig and having a nice hot meal in just a few minutes is priceless.