Aluminum bats are used because the cost over the season is less than using wood bats.
Baseball doesn't make money for colleges in the way football and basketball do.
I thought the reasons were that (1) there would be too many homeruns and fans would grow bored, since you can hit a ball farther with an aluminum bat, and (2) that they were afraid too many pitchers would get injured from lightning fast come-backers. I like your point too.