My dog eats a super premium dog food anyway, and he has lots of allergies so I don't want to change his diet. I don't really want him vomiting up his dinner all over my sleeping bag! He is allergic to wheat, corn and oats. One of the few foods we've had success with is Breeder's Choice Active Care Chicken and Brown Rice. Unfortunately I have to special order it because the local stores no longer carry it, so the shipping charges are a PITA. The maker is the same outfit that makes Avoderm and uses 100% made-in-USA ingredients. Unfortunately even the chicken and rice version of the more widely available Avoderm contains some of the allergens.
I would rather use the highest quality food anyway. Yes, it is more expensive, but because it contains less indigestible bulk you have to feed the dog less of it. When my dog was a pup in beginning obedience, the school gave us a handout comparing the cost of the various qualities of dog food. The super premium actually cost a little less per serving than either the normal brands found at the supermarket and generic dog food. Plus there's a lot less to pick up in the back yard! The minimum serving for an 80-lb. dog, 3 cups (11 oz.) per day, works just fine--he neither gained nor lost weight on our last one-week trip. At home, I have to cut back a bit on amounts to keep him from gaining weight unless we're doing a lot of dayhiking.
Sorry, I won't hike without my dog. He's an integral part of my sleep system as well as my best buddy! He's on leash or behind me on the trail most of the time, and I make sure he doesn't chase wildlife or terrorize strangers with the dreaded crotch sniff. I also treat his solid waste as I do my own. I do find that he slows me down a lot when there are people around because nearly everyone wants to pet him!