I don't really see how pointing out that being nasty isn't an effective way of dealing with someone is the same as saying "fuck that commissioner, how could they not care that you are going through _____? Your life is way more important than some art!!! Screw them!" but okay.

It's just that from what I've seen, and transactions I've experienced myself, even when you're frustrated and things are going sour that it really doesn't hurt to be civil.