Stick, the problem to me comes with the mixed stack sizes. If you have a short stack sitting beside a big stack it gets awkward. If I have a tight short stack to my left, I'll minraise to steal. If there's a big stack beside, a min raise gives him good implied odds. If I raise normally because one of the blinds is a full stack, the short stack can easily shove or at least raise and commit himself postflop.
And the loose ones that you run across are not the good ones, they're just bad players afraid of losing more money. The good ones are the ones who can pressure by raising/reraising/shoving while offering no implied odds.
Then, as mentioned, once they double up they can't play their game anymore because they start offering more implied odds, so the leave and rathole their winnings.