A friend of mine recently had 2 bikes stolen in the span about of three weeks.
He lives in a decent part of town so you would not think that you would get a bike stolen in his area.
He lives in an apartment in a house in an upstairs unit. His apartment is very small so he leaves his bike unlocked outside. He did this for almost a month and never had a problem. The bike was an x mart mountain bike that I had lying around so I gave it to him. A few weeks ago he woke up to get his bike and head out. To his surprise someone has stolen his bike and left their bike in exchange.
The bike that was left behind was in very poor shape. So he used it to get to my place, so I could try and fix up. It was in such poor shape that I did not want to put that much work into fixing a rust bucket. Luckily, under the stairwell in my building there was the exact same model mountain bike there. The person who owns the bike left it there after the back rim was stolen. He moved to another city about a year ago, so we figured the bike was fair game.
So we swapped out rims and threw the rust bucket in the garbage.
A couple weeks later, which is a few nights ago, he goes to the corner store at the local strip mall and leaves his bike outside while he goes inside to buy a drink. This area is pretty busy at night, a lot of people congregate in this area in the evening and early night. When he leaves the store he notices his bike is missing. A few locals tell him that a dude in a hoodie stole his bike. He asks another person that was parked out front while he was in the store, if they saw anything. They reply that a couple of people pulled up in a pick up, hopped out and threw his bike in the back of the truck and took off.
I guess it goes to show that no matter how crappy your bike is someone will steal it if they have the chance. Even if there a lots of people watching.