I can't say that I've hosted people on tour, nor am I member of warmshowers. I do however, empathize with how you were treated (I have to be honest, one of my hot buttons is when people don't have the courtesy on craigslist to simply reply that an item is sold/no longer for sale or simply remove the ad -I mean, c'mon, how much effort is that? Hit the reply button? It really disgusts me.) It really is sad how some people just take for granted when others extend themselves for you. Hopefully no one will ever say that about me if I can help it.

Trying to look at the "positive" side, perhaps they really did suffer a mechanical? And maybe their cell phone didn't work? Or perhaps one of them got ill and was too embarrassed to go into detail? It might really have happened. However, if that was true, and assuming they'd really not been able to contact you, I would have been extremely apologetic -and to be honest, probably not called at that late hour and waited until the next day anyway. My guess is that you had the right read on them.