Would it be possible to allow carryables to be placed into vending stands?
There are lots of good trade goods that fall into the carryable category:
HQ Logs, Barrels of <liquid>, Cauldrons, Anvils, grinders...
One problem is that one can not see the quality of those items,
and the trust between buyer and seller this demands can be considered a mechanic in itself,
but that is a separate question that probably should be fixed.