The real cost of a refund

The money coming back is the visible part of a refund. The less visible costs are the time it takes, the network fee on the return transfer, and the fact that the vendor now knows your address is one that disputes. None of those show up on the balance, but all of them are real.

A refund moves back to the exact address you paid from, in the same coin, once the case is closed. That closing takes days, not hours, because a human reads the evidence. The return transfer carries its own network fee, so a small refunded amount can come back smaller still after the fee is taken out.

Weigh that against the alternative, which is keeping an item that was not what was promised. Sometimes the cheaper move is to accept the loss on a small order and move on, and the refund is the tool for when the amount is worth the friction.