We have similar system in Europe, cc and debit cards, PayPal (And similar) payment processors remain popular.

Half the time a site just refuses to work. I click on a link to a tweet, and it’s either “Ooops…” or a sign in window. This can’t be good for a social media site, that mainly gets its value from the number of users. Disregarding laws in Europe regarding the firings is also a very shortsigthed decision that will bite them in the ass.