If he's able to patronize another business with his dollars, then the business does not have that type of power. The reason why governments are held to a higher standard wrt individual rights is because an individual generally cannot just choose another government; they are by definition monopolies.

If it were a monopoly business - say Google, Facebook, the local ISP, or Microsoft in their heyday - you might have more of a point. Few people threaten to quit Google because they may encounter rude assholes on the Internet.