This has been happening to many cars of various manufacturers but our Model S was hit as well a while back. We don't keep our parcel shelf up any longer as a result. When our car was hit it was a pretty expensive repair, $1300 I think and told the whole chrome frame had to be removed and then replaced, which added to the cost. Others reporting the same breakin reported similar costs for repair. I think from posts I've seen more recently the cost has come down...Sadly probably due to volume. And let's face it the little window glass isn't that pricy. I was afraid that the Model 3 we were buying would be a target as well since it has the same triangular window basically and fold down seats. But worse in some ways -- due to the trunk design you don't even have a parcel shelf to remove. I guess folding down the back seats is the only other option.
We spoke to Tesla during an event when the Model 3 was just coming out and brought up this crime and the expense to owners and asked them if there wasn't something they could do. They did change the chrome molding on the car, adding a seam in the upper portion around the triangular window so that only that small part would need to get replaced. If they can't get in through the triangular window, and they think or see something of value is in your car, they will then smash other windows (side or liftgate) or pop your trunk in the case of Model 3.
One Model S owner last year captured on his dashcam his and fellow cars parked near him being broken into at night in a Costco parking lot and with shoppers walking right near by. Very brazen and so quick that people don't even notice or hear it happening. Another Model S owner who apparently didn't have people walking around had his perp break the side window, flip the seat down, see something, then break a side window...couldn't quite get to what he wanted, tried to smash the liftgate, and I think ended up going back to the rear seat passenger window to fish what he wanted out. Our car was a 2 guy operation with one sitting in the getaway car. The Costco one I think was a group of 4 working the lot. There is an epidemic of property crimes like this in the SF Bay area.
With so many crossovers out there also with no separate trunk compartment and with the popularity of fold down seats, there's a ready supply of cars that are easier targets. Even if you don't keep anything in your cargo or trunk area, you are still subject to being a target of this crime and paying the price of repair if they want in your car. Many on here had their windows smashed, seats flipped and had nothing to take but a repair bill all the same.