I never share a space with other bikers unless we are riding together. If I am parking alone, I park at an angle near the center of the parking space. I once saw a cage pull into a space too fast and knock down a bike because it was parked in the front of the space and the car driver didn't see the bike until it was too late. I've also see where a cage will pull in behind the bike and park, blocking in the bike because the bike was pulled up close to the parking block in a long parking space. The biker called the cops and they towed the cage and ticketed the owner.
We pay our road taxes through gas taxes and tag fees. We bikers are just as entitled to use the roads and parking spaces as the cages.