Most bikes through out history have had mid's or slighlty rear set controls. This was probably done becasue it offers the best control and comfort. Even the old HD's and Indians with their sprung seats had controls set realtivley mid ways if you took seat height into account.
You can see that with the height of the sdeat and flloorboard placement this guy will have his feet in a more or less neutral psotion. It was the chopper era where they tossed the sprung seats and put a thin seat on the junction of rear fender and frame as well as tossed the floorboards for pegs that the ridiculous forward controls semi laying down postion were born.
This 1936 Brough Superior (sorry for the fuzzy pic) shows the usual foot peg lacement for damn near every bike ever made up the cruiser vs sportbike era of the 90's. Most UJM's employed similar peg placement to this Brough.