Today I stumbled across another example. Was on the way to my flying club, stopped in to get some treasury tags at a nearby Office World. Noticed some very nice Pilot Briefcases for sale, price £21 (inc VAT). Thought that seems a good price and bought one.
Got to flying club, and took out the catalogue of a well known supplier of things to pilots. Same briefcase - £49 (inc VAT), well over twice the cost. Why the massive price difference?