Along with weight and cost, there is a physiological problem with aft facing seats, people that tend to suffer from airsickness tend to become airsick quicker and more often when riding on an aircraft facing backward. Why I've not a clue, but that was what we were told.
CP,
Some years ago, I flew several times in a chartered Navajo with "club-seating" on bumpy summer days in Alberta. I was doing a lot of gliding at the time, so I was quite tolerant of thermal turbulence, but I definitely noticed a tendency to become queasy more quickly if I was in an aft-facing seat.
JW411,
Your photo of the wheels-up Hastings vividly takes me back to a near-head-on encounter with a Hastings west of Reading during my PPL. Exactly the same aspect, but about 50' higher!