My biggest issue is that they keep all the fees in case of a refund. Sometimes customers just change their mind, and this will cost you. It will cost you a lot if you’re selling high value items.
Same. We're losing thousands of dollars because customers change their mind or made a mistake in their purchase, mostly because we're dealing with high value items.
The payment processors are only charged a tiny fee, not a percentage of the transaction. Up until a few years ago Stripe, Paypal and others had no issues with refunding the entire amount.