Teslas do have heaters. When there is snow and ice outside you can use your phone app to turn on the heater. You can also turn on the seat heaters as well remotely. Once the windows are defogged you can get in and it is nice and warm inside. The car does not have to be driving. The same can be said for when it is 102 degrees F outside. You can remotely turn on the a/c with the phone app.