I don't see bitpay as often as coinpayments, cryptomus, bitcart, whitebit and others that just allow you to send crypto directly from your own wallet to the specified address.
you have to signup and register to use coinpayments, its not permisionless, its custodial.
cryptomus is the same. The whole point of crypto is to have permissionless direct payments, not to rely on 3rd party buinesses providing custodial services . So again, I ask where can buy something with crypto directly online as per the orginal vision of Satoshi, with no custodial third party ?
I don't use stable coins to buy anything so not sure. But if you scroll down this link there is a list of goods and services you can buy directly with Monero. Still working on it. https://pb.envs.net/?fddbb02f3599dc10#5o6C51E4iNNQC5APBegEsMRTcDsNcHUFZXEMz6RNbUhq
https://bitcart.ai Fully self-hosted and open-source, servers.guru uses it, as an example.