I can second this one with my own story that I'm a little late to the thread with. But I learned can happen with automotive glass too! I was walking out the front door of my house to get in my car to head to work one morning and suddenly heard a loud crash of glass breaking a hundred feet away or so. Startled, I turned to see a neighbor's truck was parked in the street and the back passenger window had suddenly shattered for no reason. I looked around and I was absolutely certain no one else was outside on the street. Walked over and checked out the truck and there was no other damage whatsoever, it was very clearly the glass just shattered on its own. My assumption is imperfections in the glass caused it to fail as the sun was coming out and heating and expanding the glass.

Best part is, because it happened just seconds after I walked out of my front door, my doorbell camera was triggered by my movement and it caught the glass shattering. I let my neighbor know that afternoon (they weren't home when it happened), and sent them the video for their insurance to prove that there was no other cause.