I was working at Babbage's when Bubsy was released for the SNES and Genesis. Accolade (the publisher) had somehow convinced upper management that it was going to be a huge hit so they shipped us three or four cases of the game for each system. We rarely got cases, usually half-a-dozen loose copies. So we crammed them into our tiny back room and they sat there for months. I'm not going to say we didn't sell any, but I certainly don't remember it flying off the shelves. At one point a guy claiming to be an Accolade exec came into my store asking how it was selling. Again, I don't remember exactly what I said to him but he wouldn't have been happy. Finally, after a year or so we got orders from HQ to box them up and send them back.

It was under a removable panel. If you didn't have a Sega CD, you probably didn't have a good reason to go looking for it.

It was concealed by a plastic cover which blended in to the rest of the console. It was easy to overlook unless you went looking for it.