Nice thread (if a little macabre - but that's the way I like it).
No argument about GBU, Django or The Hellbenders, but I must give an honorable mention to the sepulchre in Johnny Hamlet, which adds a deliciuously ghoulish element to that film.
And if memory serves, Corbucci includes another atmospheric graveyard in The Specialists, although it is not especially prominent in the narrative. And of course there's the Indian burial ground in Navajo Joe.
By the way, the last screen shot in Chris's post above comes close to being my favourite individual image in the genre - what a striking example of mise en scene!