In my opinion, there is a lot of buying and selling going on, but 'too much' would not be fair for me to say. (While I have truly righteous T-shirts, I do not believe in such goofy notions as the existence of a righteous person). Anyway, scenario me this: When an item is for sale and its one that I 'need' and for a price I 'must' pay and I am the successful CR-member who makes the purchase, its All Okay.
Really, in my sense of cool, the 'best' CR-reading would be of a true-life tale of vintage cycling or expert technical advice or gem-of-a-photo or whatever a lot of us would define as a neat contribution to the CR volumes: Then, punctuate that with a list -- of moderate length -- of items-for-sale (or items wanted) by the same contributor. What I mean to say is that the transactional piece is 'better' as an addendum to the pithier, punchier, or prettier comment offered. But again, that's just MY sense of cool; and its not meant to fetter or better that of other folks.
"The buyer needs a hundred eyes, the seller not one." -- Jacula Prudentum (Geo. Herbert 1640)
JB Froke, Pebble Beach CA