All sales are final is in itself illegal. As long as they can't deliver the item on the day you want your refund they have to give you the refund. That is common business pratice and even law in some countries...
That is absolutely correct.
In USA even though you can post "ALL SALES FINAL", it is illegal to enforce that policy in practice.
Moreover, a retailer must always offer a refund when merchandise is defective, damaged or otherwise not as advertised. The words "sold as is" or "final sale" are meaningless insofar as consumer protection laws always offer some form of redress.