Earlier quoted context omitted.
Interesting thought. Could there be "shunned" Bitcoins where, if they held certain blacklisted wallets in their history, businesses and users would choose not to accept them? One could imagine people still choosing to trade in these Bitcoins, but that such a penalty would forevermore reduce their value next to "unshunned" coins. Could legit businesses and people using Bitcoin collectively reduce the value of stolen B…
Who would manage such database of "shunned" Bitcoins? Who would decide which ones are "shunned" and which aren't? This is a delicate topic, almost as much controversial as censoring internet to get rid of child porn. With decentralized protocol/currency as Bitcoin is, that is not possible to do properly. OTOH, every service can decide on their own what they accept and how they operate, so each and every service opera…
It'd likely be along the lines of anti-spam lists. You might have one that's high-profile thefts or seizures. For that matter, these lists could be political, issue-based, or whatever.
It's ridiculous and unlikely to be followed if taken out to the extremes of issue-based disputes, but I don't think it's impossible for a significant number of people to agree not to transact in stolen Bitcoins, some on principle, some as self-preservation (the exchanges), and most because their utility is reduced by the first two groups refusing them. This also happens to increase the value of untainted Bitcoins.