You can't say they didn't warn you. After warning players to respect the Terms of Use agreement that they probably didn't read (because really, who reads that thing anyway?), Blizzard has acted and banned 5,000 accounts from playing "StarCraft 2" over Battle.net. Even if they could claim ignorance about what was in the Terms of Use Agreement, those banned likely deserved what they got, as there's nothing that ruins the competition in a community more than people with an unfair advatange. Heck, that's why I stopped playing "Modern Warfare 2." That, and I didn't particularly like people shooting me in the face.
Blizzard mentioned the bannings on their official site:
We recently took action, including suspensions and bans, on over 5,000 StarCraft 2 players who were in violation of the Battle.net Terms of Use for cheating and/or using hack programs while playing. In addition to undermining the spirit of fair competition that’s essential to play on Battle.net, cheating and hacking can lead to stability and performance issues with the service. Maintaining a stable, safe, and secure online-gaming experience for legitimate players is a top priority for us, and we'll be continuing to keep watch on Battle.net and take action as needed.
The moral of the story: Don't mess with Blizzard. They know what you're up to. They know about that supposedly-stealthy hack where you make all your zerglings look like flowers. They are not amused and will be coming to your house to pour gasoline on your precious desktop before telling your mom that her cooking is awful. You brought this upon yourself.