I have given up many times playing free-rolls, for many different reasons, sometimes I may get a Friend calling round for a chat or a couple of beers, So I stop playing, or I have been called out on an emergency by someone so I just sit out.
There also have been times when I get bored with the game and just jam with any 2 cards just to be able to shut the computer off and go to bed. The best part is it has cost me nothing and on some occasions I have actually made the money without even playing a hand.