Yeah, that was a cool feature. Just fell out of fad, or do ya think it was either safety related or too costly to produce.
I'm guessing it was probably safety related (or at least perceived safety related) - it was probably just deemed too make too much sense. I personally never saw anything wrong with it, I always thought it was a great idea for the very reasons being discussed.
and rule of thumb, North American cars built here gas flap on drivers side, european on the passenger side, anybody know why?
That's
partially true... there are still plenty of US cars that have the filler neck on the right side - the Pontiac G6 and the Grand Am predecessors and all of its clones all had it on the right, as did the Cavalier/Sunfire, for example. The older K-cars (Aries/Reliant) had it on the right side - and let's not forget the original Challenger and E-body Barracuda had it on the right (passenger) side as well.
As far as any reason why these cars are designed that way... your guess is as good as mine.