I don't see any mystery in why Canon is doing so well in these shops with the M cameras. I think they are perfectly designed for the target. They are small, simple to use, have a good touch screen and are fairly priced in Japan. Bear in mind that this is basically before the M5 came out, so I can only imagine that Canon will get stringer next year. Compare that with the other mirrorless manufacturers, who have been trying to push everything upmarket, and fight amongst themselves over the enthusiast market. It's a completely different approach.
With regards to the real consumer market, I think Ricoh has also got it wrong with cameras like the K-30, K-50, K-S2 and K-70. These have got bloated with enthusiast features to the extent that they put off the average consumer. They have WR, but I don't think average consumers subject their cameras to that much punishment. They have second control wheel, but this is hardly a selling point if you don't know what the first one is for. They have a pentaprism finder, but it's a bit of an esoteric advantage over pentamirror. IBIS too is a difficult advantage to sell at that level. This series of cameras is more appealing to the enthusiast on a budget than the average consumer. And for enthusiasts there is the secondary problem that the K-5/K-3 range has been such good value that most enthusiasts would rather dig a bit deeper to buy one of those instead. I did when I bought a K-5iis over a K-S2 last year.
Pentax has had some smaller, simplified cameras in the past like the K-r and the K-S1, but not every year. Look at the figures for 2011 and 2015. These were when the K-r and the K-S1 were on the market for the whole calendar year. Pentax/Ricoh had about 7% in those years. There a lot of chuckling about simple low end cameras and their green modes, but they sell. Thom Hogan said something similar about the Pentax share, "Pentax, meanwhile, is bouncing around in a fairly narrow single digit market share, dictated a bit by when they launch new consumer-oriented DSLR products."
Nikon's Slow Failure in Japan | DSLRBodies | Thom Hogan
My opinion is that Ricoh need to have at least one small and light camera in their line-up, below the K-70. Ideally it would have a good touch screen control, good wi-fi integration and be available in different colours. And it kit lens should focus silently. I don't think it's wise to avoid the low end, because it's the entry point into the system for a lot of people.
By the way, when I say "average consumer", I mean people who have no real aspiration to being great photographers or artists, but by cameras to record their vacations, children, events and so on. As I said in a previous post, BCN figures are skewed to shops in the suburbs where most serious camera buyers would not be looking.
Sorry. Long ponderous post. Congratulations if you made it this far. I am fun at parties. Honest.