On my AT thru, nearly all the hikers cooked at the shelter they later slept in. Most of the time, the hikers hung their food bags from the rafters of the shelter to avoid the "mini-bears"---mice, opossum, raccoons, skunks. In Shenandoah NP and Great Smokey Mtn NP, definitely take advantage of the bear cables. In areas where there is a hunting season for bears, bears seem to avoid humans. Most of the problems seem to be in national parks.