So what you are saying is that, in the event of an emergency, everyone has to scramble over a dead body rolling around in front of the rear exit door?
I think everyone is right in wondering if there's not a better way but, that's the way it is right now because airplane manufacturers have not planned for dead body storage.
Or they could strap the body into a jump seat for the cabin crew and a lovely stewardess could take the dead lady’s seat.
Or move the passengers to the apparently empty seats in first class.
Or stuck the body in a bathroom and closed that bathroom.
There are lots of better ways than this.