Absolutely there are very good reasons.
The first is the health and well-being of hitters. A big-league pitcher is bringing it at 90-95 mph. The only thing that even partially assures that he has the foggiest of ideas of where that baseball is going is his grip on it. Should that grip begin to slip, the ball can go *anywhere*, including right into the brainpan of a hitter, who's going to have trouble picking it up in a downpour.
Since baseball has seen one death (Ray Chapman) and more than a few careers ended or altered in bad ways from beanballs (Mickey Cochrane (fractured skull), Cass Michaels (given last rights and put in critical condition despite a batting helmet, but survived) Tony Conigliaro, Dickie Thon, Paul Schaal, Bryce Florie, Paul Blair, Mike Jorgenson, etc.) it seems like a pretty smart move.