I just witnessed a driver smashing into parked car and running away! How rude!

My family and I sat for a Sunday lunch in a pub this afternoon. It was about 11 of us. 6 adults and 5 children.
Our table was by the window and my mum in law sat on my left and my hubby on my right. We were looking out the window to a car park.
At some point the couple was walking on the car park. My MIL pointed out the hat that man was wearing. It was type of David Crockett hat with fury tail at the back. We smiled and for some reason I kept watching them getting into Freelander. The couple started reversing their truck and my MIL said 'look he is going to smack that car behind'. Next thing that happened we watched a little Pegueot moving slightly up and down as Dave Crockett stopped his Freelander. Woman turned her head back and as they both turned towards us Dave was swearing. It looked like he shouted F word.... next thing - they started to drive away. My first thing was to run outside and stop him but he looked like he is going to park and come to own up. Then suddenly he just drove off!
I looked at the number plate and tried to memorise it. I was mumbling to myself the letters and numbers of freelander plate. Went to the bar and asked for pen and paper. Wrote it down and told the barmaid that the driver of FL with this number plate went straight into that Peugeot. That he was wearing Dave Crockett hat and she said 'oh, I know who he is'. From our table we could see the bump on the bonnet, some plastic on the floor. Peugeot was 63 plate so really nice car.
Then there were some youngsters outside looking at the Peugeot and from that I assumed it's 18 year old girl who is the owner. She was taking photos and looked upset. Youngsters kept looking at our party. After a while they went back inside the pub and played pool by the bar.

I'm a bit disappointed that the waitress said thank you and not the girl who owns the car. I didn't expect the reward but simple thank you would be nice. She went back to play pool with her friends. I guess she is still young - 17, I believe and maybe a bit in shock - I would be. Her parents will be telling her off, poor kid! x

Anyway, after about 10 minutes the waitress came to talk to us. She said that the girl is annoyed because her car is on finance. She doesn't want to go to the insurance because she just past her driving test. They will try to talk to the guy (he is local painter, decorator) and see if he'll pay for the damage first. The waitress thank us for coming forward. I gave her my phone number and name because I've seen when it happened. Afterwards people told me I was silly for giving my details.

My question is ... was I silly?? Isn't that what we supposed to do??
I would like someone to stand up for me if someone smacked my car.

Also if the accident goes through insurance, what is going to happen? Will I go to court as a witness? I really am not worried just curious.

Thank you x