As someone who played no part in the 'invasion' of Thakria but whom watched it all, and answered questions for both sides, until such time as the mercinaean troops were dead, perhaps I can clear up some of your misguidances.
Thakrians did indeed move commodities around their city (whether mercinae could have got them or not is largely irrelevant, either you are saying something or you are not). However, what's wrong with this?
I know it's not permitted to remove commodities outside the city, but I see no problem in shifting commidites around in what is after all your own city (the state ministry has a nice set of commands allowing you to do exactly this). A full scale invas
ion would of course not encounter these problems since they would be able to go everywhere, and it's my opinion that this is why that rule was put in place.
Despite all the tales, Thakria and Mercinae have both behaved as badly as each other (my guess of your opinion) or in my opinion, both have made a valiant and perfectly ok attempt at getting the gold, both falling slightly short across their rainbow.
Written by my hand on the 4th of Skyelong, in the year 1068.