They should be able to. Just don't use the business. Can a rafting business require you to wear a life jacket? Can a cave or a mine tour require you to wear a helmet?

We're free to boycott and protest and get the business to change it's ways

We should not rely on government to use violence in order to force compliance from a private business, they will just use that as a precedent to use violence to force you into compliance in your private home.

They should be able to. Just don't use the business. Can a rafting business require you to wear a life jacket? Can a cave or a mine tour require you to wear a helmet?

We're free to boycott and protest and get the business to change it's ways

We should not really on government to use violence in order to force compliance from a private business, they will just use that as a precedent to use violence to force you into compliance in your private home.