Card clipping may give people an advantage, and some people may have gotten screwed out of some ballots because of it, but it doesn't worry me too much.
The reason why I don't get too angry at teams that do it, is because I know they're never going to be among the most successful teams. The people that become truly great are those that know their arguments well, research, and then apply that knowledge and work to their rounds effectively. The people that break a couple times a year and have a mediocre season are the people that cheat. I'm sure there have been some pretty successful teams that clip cards, but for every card clipper there's a hardworking team that's cutting cards right now that will finish higher at the tournaments that matter.
Maybe I'm naive, but I really do believe that card clipping doesn't give a big enough advantage to overcome teams that really know what they're doing.