Re:He should be (Score 1)

is the car company responsible for not making unbreakable windows?

No, of course not, but that is not the problem. You don't even have a window in your car, or your car can't be locked, anyone can steal your backpack!
If windows is the car, it has doors, keylocks and everything, but either the keylock doesn't work, or every car has the same key.

If someone breaks into my house...

What if you left the door unlocked? They could just walk in, grab anything they wanted and leave. They would even take the key, so they could come back for more.