In my travels through 50nl and now 100nl, you will see quite a few full time players with very low PFR% (I play mostly on Poker room skins). They look to make big hands post flop and get you pay.

Most of time these guys are raising preflop just to steal or isolate, not because they have AA or KK

I even had one of these player check down QQ on a J high board on the turn and river. (I had raised Pre-flop and missed the flop -- cbet -- he called -- then checked it down)

Once they make 2 pair or better, watch out.