Cheap, tough meat is a puzzle cooks have dealt with through the ages. The common solutions are as follows:
1) Low and Slow - cook at the edge of the fire, or atop a bed of coals, for a looooooooong time. Braising and stewing is also part of this method - adding a flavorful liquid to keep the meat moist while time and heat tenderize it. A cast-iron dutch oven is your friend. Steak chili!
2) Mechanical Tenderization - Whack the heck out of it with something heavy (back end of a hatchet or the underside of a piece of cast-iron cookware), poke dozens of little holes in it, and/or slice it thin. Beef roulade would work well roasted over an open fire, or shaved steak/italian beef/philly cheesesteak whacked and sliced on site and pan-fried in a skillet.
3) Chemical Tenderization - Acid, salt, sugar and time can make the strongest steak yield. A cheap bottle of italian dressing, a zip-lock bag, and a some quality time in the ice chest, and you have marinated steak kabob ready to be cubed, skewered and roasted over an open fire like meat marshmallows.
4) All of the above. Swiss steak! Actually, all of the above dish suggestions only work in concert with another. But seriously, Swiss. Steak.
You can do all of this in the field with a sharp knife, cheap plastic cutting board and a dutch oven or covered skillet (cast iron preferred, make your buddies pack it for you).