I was out riding last night and came across a man on the trail who had broken off his presta stem while pumping. I slowed to see if he needed help and he asked if I had a spare tube. I did. So while I dug the tube out of my bag, this guy gets out a $10 bill. He held it out, and said, "I hope you have change". I didn't. The guy continued with "I'm not paying $10 for a $6 tube!" So I stuffed the tube back in my bag and continued my ride.
What the heck is the matter with people? If the roles were reversed, I'd gladly pay extra, and would likely refuse change for the convenience of not having to walk home.