It makes all the time, money and effort worth it. I can't run to the gas station without someone coming up and telling about the time... Usually it revolves around high school, sometimes it includes a girl.
Just being able to bring back great memories for people makes I worth it.
The other thing I do is when I go to cruise-ins or car shows is allow small children to sit in the driver's seat to have a picture made. My car is a driver so I'm not anal about stuff like that.