When I was a Marine stationed in Japan, many of us rented bicycles from the shop on base. While on base, we kept our bikes locked up. Off base, you could ride over to the train station a few miles away and park it, unlocked, among the many bikes already parked there. No one locked their bikes-not even people who were traveling on the train and would be gone for several days.
Here's an anecdote that sums it all up:
When I was a Marine stationed in Japan, many of us rented bicycles from the shop on base. While on base, we kept our bikes locked up. Off base, you could ride over to the train station a few miles away and park it, unlocked, among the many bikes already parked there. No one locked their bikes-not even people who were traveling on the train and would be gone for several days.