I often do the same thing...I'll park well out of everyone's way, and I'll come back to find another Benz, or Porsche, or some other nice dent-free ride parked beside me...I'm sure they're thinking that they can trust me not to bash their door with mine, and they are right!
On the other hand, if wide open spaces are limited, I'll try to park next to a nice, dent-free car, in hopes that they care enough about their car not to bash mine with it!
One thing I NEVER do is park at an angle, taking up two spaces (seems to be a bad habit for a lot of BMW and SUV owners here in Atlanta). I've seen people get angry at someone for being an a**hole by taking up two spaces, and they keyed their car. That's just asking for trouble, especially in an already crowded parking lot.
Mike