Lifestyles of the poor and nameless

Now that the strike is over....we can get back to the real issues...lol. Like how much money are you supposed to give in a car pool with co-workers?

For the three days of the strike, my coworker "Rob" gave me a ride to work. On day one, it was just the 2 of us, since our other co-worker, Mike, decided not to come in. On the way home, Rob stopped at a gas station, so I offered to help him out with the gas. I gave him $10. The next day, Rob came to get me in the morning and then we went to get Mike. (Rob bragged the whole way about the fact that he was getting an 18% raise by taking a position in our department. Ugh!) We never stopped at a gas station, so I felt a little awkward about randomly giving Rob some money. I figured I'd follow Mike's lead for the day. But Mike never gave Rob any money and we never stopped at a gas station.

On day 3, I figured that Rob would have to stop for gas at some time and I'd give him $10 then. But again, he never stopped and Mike never gave him any money. After we dropped Mike off, I decided to give him $10 anyway. For a second there, he looked like he wasn't going to take it, but he did and that was the end of it.

I'm *grudgingly* grateful to Rob for taking me (I say grudgingly, because if he hadn't taken me then I would have gotten to work from home without losing pay. *sigh*). But I was just wondering about carpool etiquette. Any thoughts?