This happened to this Portugese (and by that I mean hot tempered) bass player in my old band. It was Christmas morning, he had no family and was totally bummed about Christmas as it was. Ended up jumping the counter and getting in a full out fist fight with the manager. Left without his food - and he'd already paid. (verified by his horrified gf, who dumped him that afternoon).
(aint nothing compared to this other story about him which left me in stitches but is o/t).
What do I do? I forgive them, and voila my food appears. YMMV.