That sort of happened to me in Ecuador...I was trying to get from Macas to Zamora, on the main road obviously, and was riding in the very backseat and the two people were chatting up a storm up front and totally ignoring me.
I was just staring out the window but it had been raining the night before and I didn't get hardly any sleep.
So I dozed off...
When I awoke several hours later we were in the middle of NOWHERE with nothing but jungle covered mountians all around us; the road we were on was hardcore mud. The driver pulled over and said that he was stopping here.
It turned out he wanted $5 because he was apparently a 'taxi' but to me just looked like a piece of crap chevy idling in the mud. I didn't have $5, so I had to give him 50 cents and my hat, otherwise he looked like he might kill me. My fault for not asking if he was a taxi beforehand, Ecuadorian taxis can be anything.
As for the road, it took me two days to get to Zamora from there...definently the long way, but it was much more beautiful, I'd say, than the main highway. I was kind of pissed about losing my hat, though