How come online games do not come down on.?

hi iv been wondering y online games mainly shooters for pc like battlefield bad Company 2 or modern warfare etc do not come down hard on hackers they are ruining the game for players that can play with out cheating.reason im asking is because i never cheat on line i do not even camp like a noob but i im just getting tried of it and im sure tons of other real players are can they just start banning accounts or have a something in place for dealing with hackers like bannig their ip address or locking them out of there accounts like give them a 3 strike rule?