Cue Nelson Muntz *Ha Ha!*
Players recently found an exploit in a single player mission of Halo Reach that allowed for a hefty credit boost. It was a minor exploit that eventually ran out of steam once certain challenges were reached. Bungie was fine with it, even publicly stated so.
However, some people too it too far, gaining points for challenges numerous times because of disconnects/bot creation. Bungie was confident in its automatic banning system. The 15,000 geniuses who thought this was a good idea have had their points completely wiped to zero, and have been given a 24 hour ban on earning anymore. That’s certainly a light warning. Kudos to Bungie for staying on top of these issues.