"damn you, Visa!" is exactly what my first response would be, either that or damning the Olympic committee. This is particularly jarring , because in the UK we

"damn you, Visa!" is exactly what my first response would be, either that or damning the Olympic committee. This is particularly jarring , because in the UK we are just used to the fact that everywhere that accepts VISA will also accept Mastercard. I can't think of a single situation I have been in where that hasn't been the case. AMEX is a little different , since most banks that offer AMEX will also give you a Mastercard/VISA on the basis that it's less ubiquitous but offers better perks.