I guess that is not a bad idea.
I also think it depends on whether you want to fix the garage wall and the car or just the car. The bollards or other methods may cause more damage to the car, depending on how big a run the car has.
To those of you think that this can't happen, mistakes happen, just ask my 17 year old daughter, who recently had her foot slip of the brakes just as she came to a stop in our driveway. Yes she hit the gas. Rear ended her moms, truck, pushed that into the garage door / door opening. Behind that door was my 74 cuda, which only had minor damage save for the bumper which was bent. Oh what was she driving, my 2016 Challenger...that I had for about 2 months. It sustained a bunch of front end damage.
So yes my new driver, 17 year old kid damaged all 3 of our vehicles and the house in one shot. It was just a simple accident, they happen!
That being said, I do think you are being a little paranoid. It may never happen! But then I don't know your folks, you do!
Good luck either way you go!