I would say that you make a good argument Mike808 but I would like to raise the point that the free coffee is not like the GPL at all. If anything it is more like the FreeBSD license. You take it you drink it, you water your plan with it, you piss it, you "Sell it on Ebay". You don't have to tell anybody anything. There is no stipulation that you must return it to the community.
It sounds like the greedy bastards who were taking the coffee home are the ones who ruined it for everybody. I don't think that the Expensive coffee is some kind of Wan Valdez conspiracy. I would suggest to management that they try an honor system where people put a nickel in a cup to pay for the cheap stuff. Or they could buy a can for free and then have a coffee rotation where everybody has to bring a can once a year etc..