Ok. Rebuttal time.
I rarely see anyone riding a "vintage" moped as a daily. Lots of crap China scooters everywhere, but no "real" mopeds.
So that kinda rules out the "cheap transportation/ congested traffic" argument. Plus there's so many damn people in cars who are out to get you. Slow mopeds are scary as fuck to ride in some areas because of bad drivers.
Southern California is expensive. So most people who actually want an old moped, can't afford them. And most people selling them, need the money because they can't afford rent. Or meth.
The antique crowd don't really care about mopeds, unless they found one in the garage of the flipper house they just bought. Then they look at Craigslist and price them accordingly.
The car culture won't openly laugh at mopeds, as most of them respect anything that's old, has wheels, and is loved by someone. But the car guys don't want them.
Scarcity could be a factor. With year round riding conditions, mopeds would wear out faster, and instead of being kept in a garage, they'd get junked.
Back in the 80's, mopeds were left out on the curb for the trashmen. I recall seeing them abandoned in alleys, stacked in piles in junkyards, etc.
We don't have barns. So it's pretty rare to find a bike that's been untouched for 40 years squirreled away somewhere.
Also, I can understand the guy trying to get top dollar for a bike he built, bought parts for, restored, etc. You know, a real moped guy.
What I don't get is some jackass who stumbles upon his old Puch at his grandparents house in Riverside, who gives no shits about it, lives amongst rusty sinks and trashed cars at his house in Norco, and tells you "...restored they go for $1900..."
Fuck that guy.