Fast pass systems are good and bad. More bad than good.
First the park creates a class system in which those customers that attend the park but do not have as much free cash to throw around now feel degraded since they keep getting reminded that others are more well off. Especially because people in fast pass lanes always seem to be so smug about skipping lines (I admit I even fall into this category a little).
Second, those that cannot afford the pass now have to spend even longer in lines than before. So by making a few hundred people happier, the park now makes a vastly larger amount more angry and spiteful. This reason really points out this is all about the money not making guests happy.
Having spent spring break and Universal and Disney, I can say the only way I approve of a fast pass system is Disney's. At Universal I had the fast pass for one day, and not the next (didn't feel I needed it on a weekday). The day I didn't have it, I felt like the park had swept me under the rug and didn't care. Disney's worked out so well it made the whole day better. Everyone gets equal access, and they spread the tickets out throughout the day so that no single person will take advantage.
I understand that parks need to make money, but when people are happy they buy more. Pissing people off will just result in people not buying anything.
Just my two cents