Lock Chain Looks Crazy, Isn't

"One Gate, Multiple Locks"
Street Use ()

Looks like urban security overkill, at first glance.

The reality is more subtle: "What do you do if you have a locked gate but more than one person is permitted to open it? You don’t want multiple keys, in case one is lost/stolen. Then all the keys may need replacing. Instead you can have multiple locks, chained into one long lock...."