I have most often seen limits abused in waterfowling. Let's face it, duck hunting attracts a lot more of the techno gadget budweiser shoot 'em up crowd. Worse yet, I have known guys who won't eat ducks but love shooting them, so they try to give them away. I think a lot of the duck hunting shows promulgate this attitude as well. It's all about killing lots of ducks, and I have never seen them hold back voluntarily, let alone focus on the romance of the sport, as opposed to the shooting end of it.
As for limits on upland birds, I think they are harder to get even if you wanted to, so I don't think that is as much of a problem. Besides, when I think of a limit of quail in my gamebag, I think of two words: quail fettucine. Yum.
