Why don't Christians do what they preach?

The Bible says to Judge not lest ye be judged likewise, yet they judge more than anyone! An example would be the movie, Michael Jackson's This is It. It's a great movie with a lot of heart and shows MJ's talent. I know several Christians who snub their noses when I mention how much I like the movie because they JUST KNOW he was a perv. Doesn't that seem contradictory to what their bible says? It says that there must be two or more witnesses before someone is guilty. Are non Christians better at giving people the benefit of the doubt and just appreciating a persons musical talent? Just wondering your thoughts. Thank you!