Why do i feel bad in some way?

I work as a Dj in Melbourne city and last night after work i was walking into the multi story car park around the corner from work. standing there at the ticket machine was young Asian guy screaming about not knowing how to put his ticket in the machine so he could pay, he asked me to do it for him at first i did'nt think about it i just assumed he was a tourist or something. anyway i put his ticket in and it said blocked, there was a woman on the speaker system in the ticket machine instructing me t0 tear up the ticket so sh could print a new one which i did. then it hit me this guy was so drunk and about to drive he was falling around extremely drunk shouting etc i told the woman i cnt let him drive she said its not her responsibility, next thing you know a new ticket was printed the guy took it and left even after i was trying to stop him driving. so i ran outside and found 4 cops whom i brought back to the car park and we caught him driving to the exit barrier i told the police it was him he was removed from the car i have no idea what he blew on the breatho though. my question is why do i feel like i have ruined this young mans life?