That's great that there are still people who will help others like that (I don't tend to find this AT ALL in much of the States...in TN & TX, I have, but not MA or CA).
With my first flat tire, that was NOT the case at all for me. I was 17 and on a busy main road and I didn't know how to change a flat back then. I had three cop cars and numerous people just pass by me...some looking, but no one stopped to help me. Finally, after 20 minutes, a guy on a bicycle stopped and helped me. I learned to change a flat on my own after that. I've also not had any help when I've fallen (not even so much as an "are you okay?"). And I've had people just stare while I've struggled to get my small shopping trolley onto the bus full of groceries...no offer of help at all.
I did have a wonderful experience in Yorkshire with wonderful people. My FIL's car ran out of gas on our way back to Hull from Scarborough. We pulled along the side of the road and a lorry stopped and asked if we needed help. He drove my husband to the petrol station down the street to fill the spare tank. In the meantime, another truck stopped and the guys this time had just enough petrol to give us to make it to the station. None of them would take any money either.