I was a kid in the early 1950s Blue, when the Malvern Star moped was probably at its popularity peak. I don't recall ever seeing a woman on one, though there may have been one exception. More importantly though, I'd say I saw several BSA Bantams for every moped.
You may have something with the "you can always pedal if the engine fails" line. There were a lot of motorbikes in those days, very nearly all of them British, and nearly all of them at least 500 cc. They were ridden by males of barely licensable age up to about about 40 I suppose, and as far as I know, all of the owners maintained them themselves. The mopeds and at least some of the Bantams, on the other hand, were ridden by people who looked as if they were constantly praying for the thing to start when they needed it, since if it didn't, they were clueless. Pedals are a useful argument in selling to people in that frame of mind. I can't imagine most people would actually succeed in pedalling one for any distance, though: they were quite heavy, and the seat seemed far too low for sustained, effective pedalling.
