Because he was a 23 year old beating up on high schoolers and low draft picks in one of the lowest levels of the minors. He doesn't have power and he doesn't have projection. The Angels have Pujols, Morales, and Trumbo, they aren't going to keep around a 24 year old first basemen with no power and projection when they can give playing time younger guys with more projection.
He is a good ball player no doubt, just not someone who an organization wants to spend resources knowing there is very low chance he even come close to making an impact.
He signed with an Indy team, the Gateway Grizzlies of the Frontier League
http://www.gatewaygrizzlies.com/pressbox/current/?article_id=439