Why are there so many misconceptions about the Catholic Church and Catholicism in general?

Many years ago I went shopping in a Christian Book store where I found, in the children's section, little pamphlets with cartoons in it attacking the Catholic Church and the Pope. This upset me so I took the literature to the store manager and asked why it was being sold here, especially to children. His response was that Catholics normally do not shop here. If people are taught from their youth to be anti Catholic, then it is no surprise that they are also so as adults.