Can anybody say RIGOR MORTIS???
Okay, setting aside the fact that bodies began to rot and decompose after time, what about the immediate effects of Rigor Mortis? Hasn't anyone found a dog or a cat that's been dead for over 6 hours? It's stiff as a board. And they maintain that same body position no matter how you turn them. There's no way you could get a dead Bernie to do all of those walking things they did in this movie with the loose legs and arms due to Rigor Mortis.
And what about the legal implications of abuse of a corpse?