A former teammate of my son's is a position player at a Pac12 school, and he also is used as an occasional middle reliever. One of the starting pitchers there DH's when not pitching. Another teammate of my son plays CF for a JC and is committed to a D1 for next year. He is also his team's closer.
It doesn't happen a lot, but it does happen. Not sure I would want that to happen at that level though. Keeping your swing and your glove in shape and also getting in your pitching work, not to mention academics - that's a lot to handle.