The buyers have lost their BTC, because Counterparty made a centralized decision to roll back the ledger, therefore asymmetrically alter the transactions which previously had occurred. This was done with full knowledge that the people who invested in XPC for the long or the short term would lose their BTC.
We didn't rollback anything. The only thing that we did was close a loophole in the parsing code that allowed for the misidentification of the source of a transaction.
+1 People need to understand what is really going on here.
Perhaps an official press release would help, rather than the aggrieved parties having to trawl through this thread, which consistently refers to the action as a roll-back of the database/ledger.
Perhaps, technically, this is inaccurate, but the fact is in the real world of commerce, transactions occurred and actions were taken; the effect being that the ledger was altered, and those transactions were invalidated.
The technical distinction is not trivial. Before the bug was fixed, transactions *which should not have been valid* were valid. The alternative you are implicitly proposing is to have left the bug in the protocol.
Also, the Counterparty protocol cannot force BTC payment, likewise it cannot reverse BTC payment. So people did not lose BTC on account of our bug fix.