Because they are sure that we will be better, that humans will be better, when we are organized globally, when our government is global. Dont dig too deeply into why they are sure of that unless you want a depressing tale of ignorance. Some of them are not sure about the better part but they think that because of our technical world and because some of the challenges that face humans must be solved on a global scale that global government is inevitable. Getting rich going in that direction is so much the better. It sounds good, that is why they did it mostly...it sounds like progress....and fuck consent.
EDIT: Yes, America has paid a huge part of the bill for this project, without our consent.....it is a major driver of the current collapse of America....it is the major reason America is disintegrating as a global superpower at record speed.