I was just searching youtube and found this:
I don't know what it is, but I love watching position players pitch. Maybe because it brings something exciting to a game that is already out of reach. Also it's an opportunity to see what a batter can do when facing pitching that might be more at home in an weekend adult league. A lot of times the batters are so used to seeing pitches in the mid 90's that they can't get their timing right for scrub pitching.