You're missing a key distinction. We are not talking about Christians simply refusing to let practicing homosexuals in their business establishments, or refusing to sell them products.
This isn't just refusing to deal with people because they are homosexual. This is about instances where Christians are being forced to commit what they believe is a grave sin against God, and violate some of their most sacred religious convictions, by actively participating in creatively planning and participating in a homosexual wedding ceremony (Such as being a wedding planner). You may not be able to see it that way, but according to their deeply held religious convictions they cannot in good conscious actively participate in a homosexual wedding ceremony.
Christians would equally choose to refuse a polygamous, beastial, or any other kind of marriage ceremony that was a mockery of the sacred marriage institution which God Himself ordained as a reflection of His relationship with His church - Ephesians 5:31-32.
It's even worse than that, though: We are also talking about Pastors who are sentenced to jail, in America, because they will not officiate the marriage ceremony of a homosexual couple.
http://nbc.com.co/christian-pastor-...in-prison-after-refusing-to-marry-gay-couple/
Even if you were to try to argue that Christian business owners aren't entitled to live by their religious convictions (which is not a standard that would hold up under the American constitution), you would never be able to justify forcing a pastor to marry a homosexual couple; because by their very act of officiating they are putting God's blessing on the union and declaring it to be a God honoring ceremony. They cannot lie about that and misrepresent God to the people. They would be forced to pretend that God blesses something which He has expressly already forbidden as a grave sin. No pastor could ever allow themselves to be put in that position and call themselves a faithful minister of God's truth.
If this ruling of punishment stands up to being challenged then other pastors around the country may be forced to marry homosexual couples; in which case you will see the majority of pastors resign their publicly recognized ordinations (which gives them the legal right to declare people married) rather than commit sin in the eyes of God. They may continue to be a part of Godly marriage ceremonies as a pastor who officiates and declares them to be married in the sight of God, but the couple will have to go to some other state recognized official to get legal recognition for their marriage.
And for the record, yes, many pastors will also refuse to perform the marriage ceremony of a couple that is living together and having sex outside of marriage. They believe marriage is a holy union and institution, and they can't in good conscious endorse relationships that have shown no respect to God's intent for marriage. If the couple will agree to stop having sex prior to marriage then they will do it. Pastors often require couples to attend pre-marriage counseling classes for a couple months before they will marry them, to make sure they are prepared for the decision they making and entering into this union with the right motives and mindsets - because helping bind two people together in the sight of God, for a life long commitment, is no light matter to a pastor. The pre-marriage counseling is also a lot of practical stuff to help set newlyweds up for success, dealing with common issues they will face during the transition. Consequently, many pastors will refuse to marry anyone who is not willing to go through some pre-marriage counseling first. Here again we see Pastors using discretion of various kinds to make sure they marry people in a way that honors God and His institution.