So you guys wanted proof, my friend made his online stats public so check it out.
You will find the 'cash earned' section of particular interest.
As background he was given 29 mil by a random in free roam. It was previously suggested my mate had glitched the cash but by looking at the 'car sales' stat it is obvious that this is not the case.
The best part of it is that he posted a ticket to Rockstar and they didn't understand what he was on about. Those guys need to get a clue and fix this game.
EDIT: I meant to post this under online, if a mod could move that'd be great.