That's really interesting and makes sense. However, given how common credit is, the fact that you must accept USD as payment in the US means that USD circulatio

That's really interesting and makes sense. However, given how common credit is, the fact that you must accept USD as payment in the US means that USD circulation is going to be really high, and therefore vendors that don't accept it for sales are going to be demolished by others that do. As opposed to BTC, where if you don't accept it, so what? and if you do, you're at least a little unusual.