Q u o t e: The thing is, once you find a way to ban them, the hackers find a way around it. Since this game is free online play, how many resources do you think blizzard will invest into stopping them. Probably once or twice a patch "which is why you see official posts with 30,000 ban's etc at a time". It would cost way to much to police the game daily and it's just not good business sense.
Do you work for Blizzard????? The cost of a simple alpha numeric security code like the ones for posting threads, to be entered prior to being able to join or create a game would be minimal. That would take out the automated ads. Now I grant that the software to auto filter char in game would take some time to create but the point is that it could be done if they wanted and would be done if they were really serious. Once the program is in effect there is no cost!