This kind of stuff isn't common, but it does happen. I have a friend who had a $10k+ bike stolen from a race. It was leaned up against a railing and he was standing about 10 feet away talking with other racers, when someone walked/rode off with it. The thief could've taken dozens of other bikes, but specifically targeted that one.

It showed up at a local shop a few months later. The guy was arrested as he was trying to ship the bike to a buyer in California.

There was also a rash of LBS break ins in my area a few years back and the thieves were specifically targeting high end road bikes. They hit at least a dozen different shops and would only steal 4-5 select bikes at a time.

Not every bike thief is a junkie looking to turn and burn something for a few bucks.