You mock, but that's the reason why they are the club they are. Without the fan base overseas they'd be skint. Rooney's goal will be worth millions in DVD and replica photo sales. Can you even begin to think of how many framed pictures of the split frame variety with Rooney on the left executing the overhead kick, and then the right hand picture of his celebration? Yep, worth a fucking fortune to them.
As for all foreign fans being Rags, well they're bound to be. I bet most Brit NBA fans are of the Lakers variety, most NFL fans will probably follow the big franchise teams, and the same with baseball. It's just how things are. You'll find a lot of the older fans in the far east will have been Liverpool fans, but I would bet they've changed affiliation over the last 15-20 years.