Oh No, PUMA People!

So there's an online movement calling itself Party Unity My Ass that seeks to... I'm not sure what. It opposes Barack Obama and seems to oppose the Democratic party because "It is no longer the party of FDR and shared responsibility. Now, it is the party of wannabe rich libertarian Democrats."

I wonder what there problem is with libertarian Democrats. All we want is social freedom (the right to do mostly what we want so long as we aren't harming others), reproductive freedom (and in general the right to make private medical decisions) and equal treatment under the law (as with the right to same sex marriges). Why should any of that bother these people?

Given that Barack Obama and Hillary Clinton agree generally on the major issues, what are these PUMA people so worked up about?