Parents...Do you get mad when someone swoops into "your" parking spot? Do you confront them?

I pull in behind them and put my car in park, right up on their bumper. Then when they get all mad, I say, "Sorry I didn't see you, just like you didn't see me waiting on that spot." Or I'll block them in other ways, like letting the car idle right behind their car. Or, if a spot opens right next to their driver's side, I'll park really close, so they can't even open the driver's side door- when you drive a 2001 Dodge Neon that's been rolled a couple times, damaging the finish isn't really a concern.