Look, if I believe that a Christian baker can refuse to make a wedding cake for a gay wedding, and I do, then a coffee shop can refuse service to anyone that they choose also. Being a cop isn’t a race, gender, or religion. It’s a job, not a “class” so move on and don’t do business with them. Easy peezy.
If you can force a baker out of business because they discriminated against an LBGT couple you now have precedence on discriminating against about anything you can imagine. I say sue the coffee shop and put them out of business just like the baker.