Currently Online 
It's a confusing thing, the businesses in their own right should be allowed to throw anyone out for whatever reason. Yet there are a few things that you have to consider in this instant. For example:
1) It's being written in law that a person can discriminate because of their faith. People are focussing on the fact it means those of strong faith can discriminate against gay couples.
2) Why is being discrimination against gay people any different to any other form discrimination? If there was a faith where someone decided to not serve someone of a different ethnicity, this law would not have been passed surely (I wouldn't give it long before this comes up). What if your faith dictates men and women should eat separately in your restaurant?
3) How would the business know it is a gay couple unless they showed affection in public or announced it as they walked in? Okay so making a cake for a gay wedding might be obvious but not other (most) instances.
4) What person owning a business purposely turns away good paying customers because of the customer's sexuality? The customer made a good choice going to that business, if you reject them, that is bad for your business only as they will tell others not to use you.
On the employment thing you mention, no one is forcing anyone to employ someone based on sexuality, race or gender (unless it's specifically required) but rejecting someone, who could be very qualified and good for the position, because of these things is not right... even if it is your freedom to do so.
Hmm, pie.
