Russia, a powerhouse, had a ridiculously complex scam going and even they were caught.

They aren't rich in the normal sense, but they are powerful and secretive, so I think they provide a valid counterexample.

Does it go on? I'd believe constantly. Does it get found out? Every time, albeit there's always a short window of success. Do more powerful nations have more success at cheating? Yeah, since the smaller countries can't cheat as well.

But not a conspiracy, just correlation, I think.