Walmart generally does not respect any laws when it comes in the way of a sale. For instance, when I was back in high school for a time I worked the electronics counter in the Barrie South location.
We had a sign up, the gist of which was we couldn't take back opened dvd's or computer games and exchange them for cash or other titles, as it was illegal under criminal code such and such.. The reason being people would rip a dvd or game, and return it etc.
I stopped trying to stick to that after a month, as when I'd try and explain that to a customer who wanted to return an opened dvd/game, half the time they would start ranting and yelling,and go hunt down my manager. I was inthe right, but I'd still get the "team player" talk... Not worth it for the $7/hour I was pulling in for that job.