It has taken me a while to get my thoughts clear about the Christian couple who have lost a case about their refusal to let a gay couple have a double room. (details here: http://www.bbc.co.uk/news/uk-england-bristol-12214368) A few years ago I would have thought they were right so I do have a certain amount of sympathy for them.
But, and it is a big 'but' why did they think they had the right to impose their Christian morality on non-Christians? I suspect the answer goes back to the days of Christendom when it was assumed that the whole population was Christian and so public morality meant Christian morality. However we now live in a post-Christendom society and we have no right to impose our views even if we are right.
We are called to be light to the world not to burn others with our morality. It is important that we treat those who we meet with love and respect and not moralising or we can never show them the joy of living in The Kingdom of God.