I love it when people do the right thing!
The other day, two 20-something men walked up to the mall Customer Service desk and told me they'd witnessed a hit-and-run accident in the parking garage. A vehicle backed into another vehicle that was parked behind it. The driver got out, looked at the damage, then got back in and drove off.
One of the men had a pad of paper, and took down both license numbers, along with as much detail as they could get. They knew the offending vehicle was a red SUV, the other a silver sedan (but they couldn't agree about what brand either vehicle was). The men's goal was to make sure the information got to the right place, but they didn't have time to stay around and talk to an officer. I wrote everything down, and watched them walk away as I called the Security office.
When I asked them why they'd gone to all the trouble. they said if the shoe had been on the other foot, they hoped someone would do the same for them.