Yeah it's REALLY annoying.
Afaik there could be more then just one factor:
1. **** cheat coders had a head start with the leak.
2. I heard a rumor that people can join ranked multiplayer games without a REAL cdkey.
3. CryTek is gathering hackers and then banning them after next patch, it's really the smart thing to do in the long run.
But after all, there will NEVER be a hack free pc fps game, there are way to many childish insecure **** pc gamers that are willing to spend money on hacks and several coders willing to sell it.
It's sad but true...