Often, the best way to make people understand how awful they are at parking is to demonstrate the effect that it has on you. When the driver of this off-road vehicle arrived at his spot to find that someone had parked their brand-new shiny white luxury vehicle across it diagonally, they decided to make a point. They rode up on the curb, and squeezed themselves into the remaining space.
With a bit of luck, when our luxury-car driving friend returned to their car, they'd have immediately realized the consequences of their own disastrous vehicle storage attempt. They might also struggle to get the driver's door open without getting a thick coating of mud from their new neighbor. If everyone parked like this, there would be cars splayed out diagonally everywhere, and it would never be safe for anyone to take a casual stroll down the sidewalk.