What's the name for the drifter/traveler subculture in the U.S.?

I’m talking about travelers with dogs that often have worn out-looking clothing, piercings and tattoos, travel in groups, etc.

Someone said this subculture is called “crusty punks” but a search for that has not yieded what I’m looking for.

Click on the link to see some pictures of the kind of poeple I’m talking about.

http://ziza.es/2007/07/23/La_vida_de_vagabundos_americanos_42_fotos.html