Thieves steal stuff to resell it.
If a product is damaged in the process, no one will buy it. Therefore, no one will steal it.
Unless someone steal stuff for one's own use. That is rare.
I won't lose sleep over it being stolen.
Besides, a side mirror probably worths much more than that.
- break the window
- pull out the trim piece
- loosen three screws
- done in 1 minute (mirror intact)