Also, if you think Amazon won't use a secret, proprietary algorithm to identify and ban people abusing their return policies (with limited to no appeal or recourse), I have a bridge to sell you.
You are correct, customers at Amazon pay for the operation that is known as Amazon and their policies, such as generous returns. Customers also shop there for the convenience of those returns.
Perhaps someday, a B&M store's algorithm will flag me as a problem customer. It's just as likely that Amazon will, though.