> In Europe, regulators were worried about the cost of interchange to businesses (rather than consumers) and capped it.

Hmm not everywhere. I recently went to the Netherlands and was surprised to see not everyone accepted credit cards - while they do accept (local) debit cards. My cards are Romanian, so you can't blame US banks.

In one small store they explained to me that accepting Visa/MC would cost them 10%, which looked insane to me.