Dear GerardM,
please just re-read what Delphine read:
Cultural differences and history are a big part of this "money changing hands" business. There are those who don't like credit cards, those who don't have them, those who would "never do anything involving money over the internet", those who have never seen or heard of a check and those who can't imagine that checks are not accepted, those who love cash and those who hate it, those who are paypal freaks, those who don't trust paypal. In short, there are as many ways of "paying" as there are countries and people. And one organisation cannot accommodate them all.
A public discussion about how to pay based on different background and limited knowledge of concret circumstances is a wasteful effort of time that can better be used in other places to help Wikimania and the other Wikimedia projects.
Greetings, Jakob