Ha, I used to get a discount for that on my civic. The dealer etched the vin and tried to sell it to me for $150. I said I wouldn't pay. They said I had to, it was already there (they did it on every car). I said 1) drop the cost, 2) change the windows, or 3) watch me leave. They picked #1. But I wouldn't be signed up with the company that does it, so i was not eligible for the $500 if my car was stolen.
But I still got the insurance discount. It is considered a deterrent to the insurance company. So over the 8 or so years I had it, I came close to the 500 in savings.
