As I said, I live in a good area of the city, in a nice neighborhood. A few years ago now, someone knocks on my door. It's my neighbor. They proceed to warn me that they had a drunk/druggy (in my view, possibly illegal alien) walk into their house a few minutes ago, and he left after they pointed a shotgun at him. So apparently, they at least did leave their doors unlocked. I don't know if they still do or not.
A few minutes later I needed to leave and as I was pulling out of my garage, several sheriff cars and officers were arriving in the area. They didn't stop me but did seem to be looking in my direction, possibly for any signs of me being involved in whatever about this druggy (like a hostage situation, he could've been inside my house, in my truck, in the back of my truck etc.)
IIRC they caught him walking again a couple miles again from our neighborhood. As it turned out, the druggy was at a bar a few hours earlier and stabbed someone, so LE were already looking for him. He had then walked about 5 miles, I guess arriving at my neighborhood and decided to walk into their house, which all sort of makes sense with his path. Who knows what might have happened if they (couple and their 3 younger kids at the time) didn't have a gun, and or further not able to defend themselves against a drugged out knife maniac.
I don't think he tried my house but he might have, and he might have tried another house or two..I don't know.
So the thought of someone just randomly walking into my garage and possibly taking off on my bike? Doesn't seem too far from a possibility that can be avoided most likely by having the keys in the house behind a locked door. It's a small precaution that can save a big headache.