While some say the bicycle became a kid's toy after the 1920s, I say that's mostly, but NOT entirely true. While marketers turned their attention to kids, there's plenty of pictures of adults still buying bicycles for themselves. Even my Huffy catalogs still marketed some models to young adults. Marketers changed their tune in the 1970s when fuel prices went high and the environment became a concern. Roadbikes became king.
Detail was not exact on anything "back in the day". There was a margin of error. Cars, trucks, motorcycles, bicycles, etc. nothing was exact. Nothing we discuss on this site was collectible when it was built. It was an item you used daily and as such, the job of the factory was to send 'em down the line. Some emblems on cars weren't exact, or engines got changed out when there was a shortage or a strike. Bicycles? Seats, grips, pedals, or even tanks or chain guards were swapped out to get the job done.
For me to say that something is truly an anomaly, it would have to be so different as to fall outside of the margin of error. Say, a bike being painted a totally different color than what was even optional (take my black Huffy Impala for instance). Perhaps a model that was so unique, it didn't fit in the normal way of things when new (Bowden Spacelander). Or a special frame with a serial number past the time it was supposed to be sold (like the OP's Colson).