Another way to look at it..... Walmart has low-end sporting goods for the most part, for the beginner hunter, fisherperson and camper, which IMO is the vast majority of the public.
The others, Bass Pro, Cabelas, and Gander Mountain, cater to more of the high end, more experienced sportsman,(more choices, better quality items) and is much less of the overall market. (Note: you can't even get a $100 Jack-a-lope at Wal-mart, LOL)
Rob