Just a thought who pays for all these summits?

Being as there seems to be some "World saving" meeting or summit nearly everday now, I was just wondering, A) Who pays, & B)how much does each one of these cost?
I bet each representative comes with a few hangers on as well as their important staff, Fuck me + security, transport, food, accomodation....There we are no more meetings and we have already saved some money!