Why do hippies have dreadlocks and refuse to shower?

OK, I understand that not all hippies wear dreadlocks or refuse to shower. And I happen to live in a town where there are still a lot of hippies, young and old. Now that we've gotten that out of the way, why is it that hippies wear dreadlocks and refuse to shower? I can understand not wearing coorporate clothing (i.e. making your own clothing or buying recycled clothing), and I see why people choose not to shave, but I still fail to see the point in wearing dreadlocks or refusing to shower. All I can think is that maybe hippies conserve water by not showering, but the dreadlocks I'm lost on. Please explain?