Never boondocked at a cemetery but I once did a garbage dump, totally by accident.
Late, very late one night I couldn't drive any further, pulled into a nearby town, drove through looking for a place to crash for the night.
Turn here, turn there, found a road leading away from residential streets, pitch black, not a light in sight. Dead tired... Pulled into an open area, couldn't see much around, good enough. Climbed into the TT and went to sleep.
Woke up the next morning, hmmmmmm, smells a little funky here...
Stepped outside, we were in the middle of the local garbage dump!