This Toonerville Trolley was based on a windup floor toy. Lyle Caine Sr. made them in much brighter colors for "O" Gauge, Standard Gauge, and (I think) No. 1 Gauge. His trolleys had black windows with a figure of the Skipper as motorman.
Other figures, the station, and that turntable were later additions. A figure was placed in each window, too. I vaguely recall seeing a trailer for the trolley at York once or twice.
The trolley would have looked strange running in reverse, so someone came up with that turntable. The trolley wobbles onto it, bumps the switch, and turns around. Then it goes back.
This turntable must be an early one because it isn't painted.
As colorado hirailer posted, such turntables were used to turn small railbuses.
Some inspection cars had a plate under the frame. It could be lowered between the rails. Raised off the rails, the car was turned around and lowered onto the track. The platform was raised, and the car was ready to go.
An ingenious bunch, these railroaders!