Anyone who holds or is thinking of buying SBC will care what the "religious wackos" think if/when SBC starts getting dumped becuase of poor choice of logo. Horns is definitely not a good idea; people might associate it with devil, and the "S" with Satan, and red with the devil.  This will deter 2 kinds of people from SBC:
1. Christian / religious types.
2. Non- religous types, don't give a damn about the horns per se, but even they might be worried that the horns will scare off the religious types and therefore limit the appeal of the coin.