I think having a place where people can discuss wanting to exchange Pinoccios is a necessary part of the community. Going through a "more appropriate resale channel" like eBay would be a possibility, but unless there was somewhere in this community we could list that modules were needed or available for sale, setting up that sale would be difficult. I think posting disclaimers is a good idea.
One possibility is you could make a "Marketplace" category with the appropriate disclaimers, and people could post there. There's a category "mute" option in Discourse so that's one way to filter out chatter if you're not interested in buying or selling.
By the way, I'm selling my boards because I don't see myself using them in the next year or so, but I'm not leaving the community. I'm still interested in what's going on and have a project in mind for sometime in the future, and hope this community is still around when I'm ready to work on it.