A person I knew from years ago at university, "John", contacted me out of the blue today. I had never liked this person, who was well-known to like nothing better than inciting arguments, and would bicker just for the sake of bickering. Needless to say, we were acquaintances only because we shared so many classes.
I am a very casual artist, and when I have the time, I do highly-detailed pencil sketches wherein I aim for photo-realism. These take upwards of 8 hours, and I've had several commissioned and sold for a few hundred dollars each. John remembered these drawings and wanted me to do a sketch of him. I didn't particularly want to draw someone I dislike, but would have felt guilty for flat-out saying no, so I said sure, and told him the usual prices people had paid in the past.
His response? "Oh, I know other people have to pay and stuff, but we both know I don't have to, thanks. It's just a drawing." He wanted 8-12 hours of work for free. If we were best buddies and it was his birthday or something, then I might do this. But not for this guy I hardly knew and found what I did know unpleasant. It took me quite a bit of effort not to tell him that if it was "just a drawing" that was worth nothing then he could bolly well do without it.