From over here it seems that your political dynasties are at least as prevalent as ours are, if not more so. It's not just democrats either. We have a number of father/son successions to political office (mother/daughter one likely to happen at a by-election soon). There is a political class in both countries, and it seems to me that the general populace for all the bitching and moaning is happy for the same names to reappear, the same training in student politics etc to give rise to the same old politicians.
It sucks, but I'm afraid you're right. I'll never forget some of the crap I heard after JFK Jr. died. In their fawning, one reporter made a comment about how the kennedy's "are the closest thing we have to royalty." I was 16 and less jaded than I am now, but my first thought was "wtf, didn't we fight a war so we wouldn't have to deal with royalty?" When I mentioned my thoughts to a few people, I got responses ranging from blank stares to "why are you being so insensitive?"