Part of the problem with FCA are the uneducated families it attracts. Part of it also are the Catholic families who think sports is the most important thing on the planet.
Add them together and you get obnoxious parents on the sidelines. The only other parents who can compare are Madlax parents.
Why point out the Catholics? I have seen just as many Jewish parents act like asses on the sidelines, though, I don't necessarily ask the jerk parent what their religion is.
More anti Catholic bigotry.
