Why no seatbelt for rear facing dinette seats?

Here is the latest on which states require rear passengers to be belted in:

"In the following states, the law is that all passengers in the RV have their seat belts on, regardless of where they are located in the RV":

Alaska
California
Colorado
Delaware
Washington
D.C.
Georgia
Idaho
Iowa
Kentucky
Maine
Massachusetts
Montana
New Hampshire
New Mexico
Oregon
Rhode Island
South Carolina
Utah
Vermont
Washington
Wyoming