Mine is like that too, and I think it's kind of handy. I keep tools and flashlight in that compartment along with the other stuff that's permanently there, and I can access it just by pulling up a cushion.
One other thing, although my trailer was stored in a barn, I have been amazed at the lack of bugs and critters in it. I have spent the last couple weeks cleaning it, and have not found so much as a spider. I thought I heard a mouse the first day, but never found any evidence of one, so hopefully it left and went to live with the other mice in the shed! A tip from the previous owner said that when the trailer is hooked up and there are cords and hoses hanging down out of the utility compartment, stuff the remaining space in the access hole with steel wool, and the mice won't be able to get past it and invade.