It is hard to close a loophole like this due to the sheer volume of traffic, I mean we are talking like 2k clicks and $10 gone in 3 minutes.
They use to allow you to update your daily budget as much as you want, so I would be spending $10, cap it, then up it $10 more and so on, but now they have fixed that issue, mind you there are places you can still do this and make some really killer bank =)
As for the volume of pubs possibly doing it, most will never take action, or just won't get it. There are also a few other variables that come into play regarding if a campaign is going to be successful or not. I'm running a few accounts and max campaigns on each and I have no problem with getting clicks, the volume is there for sure.