I think that lift-surf is a very dangerous and crazy practice. Teenagers can be seriously damaged (hurt) or even killed. It would be better that they don’t practice this sport.
Teenagers practice lift-surf, I think, by the emotion of risk quickly related with the years of age of these youngsters.
Teenagers could do many other things less dangerousness and less stupid than to ride on top of the lifts up and down of flats. They can do sports (basketball, handball, tennis, swimming….)
In my country, teenagers go to the disco, play to computer games, go to see movies…
When I was a teenager, I use to go to the cinema to see movies, to the beach in the summer and to dancing parties with my friends.