I've seen many bicycles locked to keep them from being stolen, as well as scooters. I'm not sure if motorcycle riders have to use this type of lock. However, this is the first time I've ever seen a tricycle looked to a pole.
This was in Venice Beach, CA, which looked as if it had seen better days. It was a stop on the LA tour, but it's time it was taken off the tour.
I was just surprised to see the tricycle like that. The family probably lives in an upstairs apartment, and they don't want to carry the trike up and down the stairs.