I am no expert but I would assume that a low income Walmart would be a better gamble. I would assume that video games are not high on their list with their limited income.
Not really sure it matters by income IMO, low income area might go crazier for "deals". I would think it matters more by the amount of traffic the store gets.The "out of the way" stores might actually be the best bets - although they might also get less inventory. I do feel that the more rural stores are usually the best for clearance finds and such - it might also apply to black friday/thursday but I'm not really sure (Wal-Mart is not a place I'd want to go for black friday LOL - just isn't worth it to me).