Say that someone helps you change your tire, or otherwise fixes your car when you're pulled over on the side of the road. Besides profuse thanks, do you offer them anything else: cash, to pay for breakfast or coffee, something else?

This happened to me recently, and I wasn't sure what to do. On the one hand, I was incredibly grateful and wanted to show my appreciation. On the other hand, if someone is helping you out of a good Samaritan impulse, then it feels a little rude to offer money?