I did this in Copenhagen a few years ago. I wanted to take a bike out a few times but could never find one at the kiosks. I finally did find one and I took it out. It rode like a lead weight but overall it was a pleasant experience being able to ride around with all the other cyclists there, and there are a LOT of cyclists there. The cyclists outnumber the cars. The final note to this story is that it was World Cup week (just like now) and I went into a bar and didn't lock the bike up or put it back in the kiosk. I wasn't in there for long, I was just bringing a beer outside, but the bike was gone. Oh well. In Copenhagen there are bikes parked everywhere and I would think theft isn't a problem so I don't attribute this to theft as much as another drunken guy needing a way home.