Normally I don't like pirating stuff (PC programs) - but when it comes to games then I'm afraid that's usually all I do (note only DS games & not Wii etc).
Normally you read such a great review about a game that you think you REALLY want to play it,
So you go out & buy it (~£25-45 depending on the game system it runs on)
However after a while you find the game loses it's appeal, perhaps too repetative, or you find the control system is not too your liking - whatever the reason you then think 'this is really a waste of money'
Of course that's exactly what has happened - you've spent your money on a supposingly great game, & you find out it's not as good as you were led to believe... therfore money wasted. The only option is to dump it in the bin or try & sell it on to try & get SOME money back
I WILL buy games if I really do like it, or it has some extra add-on appeal (On the PC for e.g. I happen to have virtually all of Halflife 'series'), but personnally I don't feel guity on pirating games