Well, it does matter, because it does cost money to run the heat so long, and it can consume more time than a person wants to spend before he can use his car.
My car is parked outside, and I have had a few instances of difficulty with ice on the windows. My personal opinion is that the frameless windows are one of the worst design features of the Tesla. I can't see their value, in the first place. They require the window lift mechanism to lower and raise the window every time the door is opened, putting much extra wear on an expensive mechanism. Frameless windows don't seal as well and are more prone to rattles. And they are prone to problems in the winter.
Woe betide the person who does not thoroughly scrape or melt the ice off his frameless window, and then forces the door open. Once it is open, the door cannot be closed if the window won't retract because of ice. (I know, I have done it.) So one must be patient and either wait for the heater to melt the ice (slow), or scrape thoroughly.
I love my car, but this is indeed one of those design details that those us who live elsewhere blame on the "California thinking" inherent in certain aspects of the Tesla. I had hoped that the Model 3 would get away from this rather impractical design, and am disappointed that it does not. This is my first car with frameless windows, and it did not take very long for me to develop a dislike for them.
By the way, by coincidence I had a test drive in a BMW i3 at an EV event last week, and noticed the i3 also has frameless windows. The way I noticed it was wind noise. Despite BMW's reputation for fit and finish, there was noticeable wind noise from the driver's window at highway speed. (There was much less road noise than in my Model S, though, which made the wind noise more noticeable.)
