Never failed when I had my 350Z I would park 6-10 spaces away from everyone else walk the extra 30-60 feet into the store and I could be in there for no more than two minutes and someone would always be parked right next to me. It wasnt a once or twice thing it was a everytime I took the car out type thing.
If it starts happening to my 370z I will leave orange parking cones in my trunk and put them in the spots to my rear and sides. Let someone run one of them over or move them. I will take a steaming dump on their hood.