It looks really nice with the doors. I do think it is for safety reasons why they were added. I remember being really little thinking "I could fall out of this."
People would always have limbs etc hanging out when they were carrying strollers, kids etc.
I would think that if it was in place for people exiting the wrong way wouldn't they have put automatic doors on so they can control them like they do on the monorail? Only one side would open upon exit.
Do both sides still open upon stopping to exit?