VIN numbers on the windows of UrQ

[WLAMB@denver.echobay.com]

     I was checking out a rather tired early '80s white UrQ
     in my parking garage today. What struck me as odd was the
     VIN numbers were etched (scratched) into the door windows
     and rear window along the base. Are these windows so rare that
     the owner was afraid of theft? What is the deal, was this OEM?  Last
     summer I talked with the owner and she said was probably going
     to part with car someday soon.  I told her to let me know first.
     Another project car for sure..
     
     Bill
     89 200Q still with broken driver's lock but I have the parts
     but not the right torx socket yet.