Lots of people don't and most don't have their cars vandalized. It's unfortunate what happened to that CTS-V. Unfortunately, it could have happened to a friend visiting the neighborhood, too. A garage doesn't protect a car after it leaves its protective sanctuary.
A garage is great for when the car is at home but when the car leaves its sanctuary then there is risk. Perhaps if you never stopped at a restaurant, shopping center or motel on an overnight road trip then you could claim that you are secure. Thieves will hit you anywhere at any time. I'm with Diber and Eric, invest in some good quality locks! But rule #1 is NEVER leave anything that you value visible inside the car.
The $95 will be much cheaper than the time, expense, disappointment and frustration that the CTS owner will experience having to deal with the hassle of replacing all his wheels. Yes, I know insurance will pay most of the expense.