I forget where/when I read it, but I was surprised to learn that there are a lot of rules would appear to be the same but are just different in the NBA and NCAA. For example, the definition of a block/charge - in one case, it is based on foot position and in the other case it is position of the torso. I don't think even the most observing of fans realize these minor differences, so it just looks like one set of refs is just bad.
I think refs on all levels make mistakes, but I also think that they probably know a little bit more about the rules and how to officiate than I do.
I'll still yell at them, though.