It may had been over twenty years a go since I first played Sonic 3 & Knuckles, but I remember instinctively knowing how to get pass the barrels the first time I encountered them.
They were going up and down, so made sense I mimiced their movements with D-Pad.
Good for you then but majority of gamers back then took times to figure it out since that kind of control wasn't in manual book.
But game accessories are the coolest! Whenever it be Retro-Bit recreating classic controllers for modern PC, or modern controllers with Sonic-style to them.
Plushies, shirts, and Figures sold a way more than controllers.
You must understand that most of people who bought SEGA merchs aren't gamers anymore.
They are adults who almost don't have time to play games anymore or even don't play games anymore but they still have a soft spot for SEGA / Sonic related things so they buy those to put them in their bedroom, guest room, or even office room.

this is another reason why SegaStore should market other products. I don't want to get an Insertcoin account just for seven items at best. If SegaStore account allows you to purchase other products as a middle-man, that be great!
Though my best hope would be to hope Insert Coin has an official eBay account if I want to buy the products.
I never have Insert Coin shirts.
Their shipping price to my country is just too expensive.
Last SEGA related shirt that I bought was from Uniqlo.
This one (the left one) :
