As speed said, we can't read EVERY post in EVERY topic. The forum is just too large for that. The report button is there for a reason, so instead of moaning that things aren't on topic / are getting a little bit out of hand, report it! We'll deal with it and then everyone's a happy chap. One of the main reasons arguments and off topic posts get out of hand is the fact that some members' internet ego's are far too great for them to just let others get on with it. They need to sort it out, and then they're just going to cause more trouble.
So instead of whining that things aren't being done, just use that pretty little button. We'll deal with anything you report (unless it's stupid, of course!) as soon as we see it (as the staff room is at the top of the forums, it's the first thing the admins and mods see)