Is it absolute necessary to have these stupid foam like foam back? Because according to my common sense, these thing don't so anything. Well, maybe sound proofing and others. But mine is already snapped in half and was like a pile of ABC bubble gum.

There are 4 pieces of sponge down there. (Pick it up) using tweezers.

Well, I have none. Still, it is OKAY to do it with or without one.