Umbrella Theft?

This afternoon I went to the National Art Center to see a collection of work from Picasso.  I figured I'd make it to the museum at least once while I'm here in Tokyo because it's a 2 min walk from my house.  Since I couldn't take any pictures inside the place, I decided to look around out front to see if I could find anything interesting to photograph.  My discovery was this small complex built to hold and lock umbrellas, that's it.  I know it rains a lot here but is umbrella theft a big problem?  The structures holds about 400 umbrellas at any given time.