In the example I used, the printer did not lack the capacity to fulfill my order. He had handled much larger orders for me in the past. He just didn't want to do it at the time. And I was okay with that. I found another printer who was happy to get the job.
As a business owner with a printing business, I want the ability to decline printing up posters and tickets or whatever for an anti-gay rally that I consider to be unethical and wrong. In fact I would not accept such a job. Neither would I interfere with or attempt to punish those who chose to participate in such a rally.
So even though I personally have no problem with attending or participating in a gay wedding and have done so, I would also allow a printer to decline printing up the announcements or whatever if he had moral convictions against that. And I would expect him not to interfere with or punish those who were involved in that wedding.
Tolerance must be a two way street or it becomes arbitrary and authoritarian dictatorship imposed by whomever has the most power.
Therein lies the problem.
Disclaimer: The following response uses the term "you" and "your" in the 3rd person only, no ad hom is intended.
If you went to your public library and asked them to procure a book by a racist white supremacist they would order it for you if they didn't have it in stock. The individual librarian doesn't have to agree with your reading tastes to provide the book. They just have a professional obligation to provide the service that you requested. The book you request could be about gay pornography and the librarians would still be obliged to provide it to you even if their personal religious beliefs were opposed to gays.
Why does the printer get a pass when the librarian doesn't?
Librarians don't make judgments about people based upon what they are reading. The reason you asked for the book by the white supremacist might be because you are studying the subject for a college course. You might need the book on gay pornography because you are researching a paper for your thesis.
So why does the printer get to pass judgments on what he is being asked to print up? Does he just assume that you are a racist white supremacist when in fact you are using the materials for a documentary film that you are making?
The simple fact is that the printer, the baker, the candlestick maker, et al, don't get to pass judgments based upon their personal religious bigotry and refuse to provide products or services without suffering the consequences of the actions, or lack thereof.
When you are acting in a professional capacity you do your job which is what you are getting paid to do. You are not getting paid to impose your personal religious bigotry on anyone.
This has nothing whatsoever with "tolerance being a two way street". It has to do with the OP erroneously conflating two entirely different things. You, as an individual, are entitled to whatever religious bigotry floats your boat. You, as a professional, cannot deny other's their right to equal service because of your personal religious bigotry. Conflating them is a fallacy and can never to legislated without causing harm and denial of rights to individuals.