RE: took 1 in the a$$
I do my own for that very reason... I don't trust some guy not to chunk off a few of my tenderloin backstraps for his own frying pan. In your case, you just plain got robbed. I agree, the butcher doesn't have access to elk and wanted some. He may even have sliced one off to try. After trying it he decided he wanted more. He's just a crook.... or, the people that work for him are. That's a big possibility.