Feel that the bigger issue here is that of transparency and clarity from a seller.
In the open, don't think buyers mind too much about how the items are sourced ie. if they are stolen, grey market, with/without invoice etc., as long as they get it cheap enough.
But in a community such as here, it is imperative that some degree of self-policing takes place (within reason), both by mods and members alike. In the sense of "looking out for each other", say.
Like in the case where *reasonable* suspicion (backed by at least some degree of factual proof, IMHO) arises, of a seller selling stolen or illegally acquired items (the prime focus of this thread). Or a case of a seller (or even the buyer, in a complex case involving returns/refunds) intentionally withholding legit information or documentation essential for a fair sale, either by refusing to reveal it on request, or by remaining silent. And, the sale thread implied in this thread already by several others (me included), almost certainly comes under the latter.
It is my belief that any member must be allowed to interfere in a sale thread, to raise genuine queries/suspicions, as long as it is fact-based and relevant to the sale. This may occassionally mar a deal between the seller and a willing (and/or gullible) buyer, and yet may be the right thing to do.
At the moment, I feel that sale threads are forcefully restricted (perhaps a bit too rigidly) to the seller and potential buyers alone, with a certain mod deeming anything other than a "bump" or a "pm-ed you", worthy enough of categorical deletion. Again, just doesn't feel right.
Bro I think this is what the OP i.e me is trying to emphasize.. , but you have written it in a much more understandable manner. Cheers...