3 words.
Piracy IS Stealing
Really at this point in time it isn't about the third party developers making games for the vita as they are the ones who are going to get effected. In turn if games stop coming out you are directly effecting vita owners who bought a vita, bought vita games and overall supported the people developing games for the platform.
Really the problem is, I and many other vita owners, are annoyed. We're annoyed because of the potential effects piracy can have on a system like the vita and we're annoyed at the selfish people who want to pirate stuff.