Most retailers just have a standard return policy, it's a good idea to choose where you purchase a major appliance where you know the return policy.
For Costco it's 90 days for a major appliance, you don't have to justify yourself as to why. Some stores have terrible return policies, some have good enough policies.
I've seen snap together flooring, the kind that does not require nails, returned to Costco full of nails. I thought that was incredibly wrong but they took it back
Yeah, good return policies make things easy, for sure. But retailers with bad policies still have to fulfill their legal requirements even if their policy conflicts.