Clergy have every right to refuse them. Other people have every right to express their views in peaceful, democratic fashion, e.g. picketing such churches, just as they would with a church that advocated any other distasteful view.
No-one, those bakers included, is legally compelled to support gay marriage. Some people may find themselves economically compelled to do things they find distasteful, but to a certain extent that's always true for anyone who has to work for a living.
There are some things that we consider it unfair to economically compel people to do, e.g. OHSA. Do you think that should be extended to e.g. making it illegal to make someone's job contingent on officiating gay marriages? What is the natural boundary there - should it be illegal to fire someone for doing something they're politically opposed to? Should a barman have the right to e.g. refuse service to women because they don't think women should be allowed to drink?
It's not that clear cut. Could a business refuse service because the customer is black? Could a town effectively segregate gays into separate but equal neighborhoods, with separate but equal businesses, churches, schools, etc?
No-one, those bakers included, is legally compelled to support gay marriage. Some people may find themselves economically compelled to do things they find distasteful, but to a certain extent that's always true for anyone who has to work for a living.
There are some things that we consider it unfair to economically compel people to do, e.g. OHSA. Do you think that should be extended to e.g. making it illegal to make someone's job contingent on officiating gay marriages? What is the natural boundary there - should it be illegal to fire someone for doing something they're politically opposed to? Should a barman have the right to e.g. refuse service to women because they don't think women should be allowed to drink?