Version: 1.0.9 Rev B (from Steam). While going through the first floor I ran into a Monolith standing on top of a mini-fridge (both on the same dungeon tile). When I moused over, the text indicated a mini-fridge. When I clicked, though, I got the Monolith message and the fridge didn't open.
Confirmed on Win7/64. Mine was a Monolith on top of grated cheese and another on top of a potion. Fwiw, I have never found anything inside a fridge, charcoal grill or the statues that announce "heroic vandalism".
Use a knockback skill or a Handy Wand (if you don't have one now, you will find one eventually) to push shrines around. It may take a few tries, and be careful not to push them through a wall.