I have noticed hobby shops keeping less inventory of hobby rocketry products than in the past (If you want to go back 50 years).
It seems to me that back in the 1970s hobby shops carried much more inventory and variety of rocketry items. Not every hobby shop but one was likely to see much larger displays of rocketry items than today even with more hobby rocketry manufacturers.
I remember talking to a hobby shop owner over thirty years ago at a hobby trade show. He said he liked rocketry because all he had to do was hang it on a peg and it sold. Perhaps the rocketry manufacturers have made the product too easy to sell so there is less involvement by the store staff in the sale of the product. I know that when an R/C truck is sold there is often a bunch of aftermarket parts and things that can be sold for use with the truck. My experience selling R/C cars in hobby shops decades ago involved selling the car kit, R/C radio, battery and battery charger each made by a different manufacturer and plenty of options for each of these items. Then you could add on aftermarket tires/wheels, more powerful motors, etc.
Maybe rocketry needs to be more difficult to undertake so that hobby shop staff will have to know more about the product and how to sell it.