Europeans also have the hurdle of telling their bank in advance that they will be using their card outside the EU, which means even if they hold more than one card, they may only make the effort to make one card active in the US, leaving the others behind.
For which European countries and/or banks is this the case? I have a Dutch bank card, two Dutch credit cards and one Belgian credit card. All 4 have been used in Europe, Asia and North America without every requiring bank notification. I'd hate to run into a problem checking out of some side of the road hotel at 4am CET one weekend..