Sorry I have nothing useful to add to the OP:
But a little courteous and pleasant attitude goes a long way, especially when dealing with something like this. I won't do so business with people who act like I'm bothering them, I don't care how much I may want whatever they might be selling. Does it hurt that bad to not be a jerk to someone who wants to give you money?
(and this isn't directed at the people at glasscages, just jerks in general)