I just want to briefly comment here on the notion that VAC is designed to generate revenue. It is not and it never has been, and it doesn't make sense to even believe so if you think about it for a few minutes.
Let's say we ban a cheater, and then they rebuy the game. This generates 1x revenue, for the cheater's repurchase. But that cheater negatively impacted the experience of N other people (where N is greater than 1), who had less fun than they would have due to the cheating. Some percentage of those people are not going to buy in the future because their experience has been bad, and they may _never_ buy again. That costs on average far more than the 1x you got from the cheater rebuying, and it compounds.
We would much rather have the cheaters out of the community entirely than have them serially repurchase and screw up other people's games.