Why aren’t car windows made out of something non-breakable to deter thieves? Or simply laminated like a windshield?
Probably because they want you to be able to break them and escape in the event of an accident or emergency. What would you do if you accidentally drove into deep water?
Nothing is really “non-breakable” the question is just how and when it fails. The calculation with glass in cars is that the most important issue is rider/driver safety, and that means a failure mode that doesn’t produce large sharp shards of glass, polycarbonate or whatever material you want to use. It’s also helpful if you as someone inside of the car have a prayer of escaping in the event of an emergency that makes the doors impossible to open.
Thieves are a pain, but not so much as being decapitated by a flying blade of window glass.
Basically it’s more important that the fire department or the people inside the car can break the windows without heavy equipment than to make ot thief proof. Making it thief proof would make the car a potential death trap. Also, a “professional” thief would just bring a portable angle grinder with a diamond blade to compensate anyway.
So you can get out in case of emergency.
Tempered glass is also stronger which would likely work much better for side windows being rolled up and down on channels as it needs to retain it’s shape.
Imagine you are trapped in the car, door won‘t open, shit‘s on fire, and now you can‘t even shatter the glass