Wal-Mart is in a no-win situation here. If the stores greatly restricted returns (which isn't a bad idea), people would complain loudly about that. It's obvious that the return policy is far too generous now. Another thread, if I recall correctly, said that returning used oil in new bottles to scam Wal-Mart is a common problem with illegal immigrants.
My previous employer, an electrical supplies wholesaler, had a new CEO in the early 1990s who told all the branches that henceforth the policy would be to allow customers to return anything for credit up to $200 in value, no questions asked. You wouldn't believe the nightmare we had with contractors returning material that we didn't stock. Some was even material from manufacturers that we never did business with. And, yes, sometimes the items were used, which is bad news for many electrical goods.
The rationale for the new policy was precisely that the big box retail stores had such liberal return policies. The CEO forgot how prone commercial contractors are to attempting scams. Don't know if this return policy still stands; I left the company not too long after that.
Liberal return policies, including allowing returns without receipts and allowing returns after indefinite periods, cost all of us.
By the way, just
why are you buying oil from Wally's World in the first place? Ain't no GC, Royal Purple, Red Line, etc., there. Thank goodness.