That is the point there is no grey area, you are either accepting or not there is no scale. Someone would be harboring these feelings before they say "that's it I'm a gay hater because of the B&B or Cake cases".
Think about it this way, it was enshrined in law that practicing homosexuality was a criminal offense and a lot of people who are alive today still probably think that way after all it was only decriminalised a few decades ago. So what wrong with a law ensuring that gay rights are now protected ?
There is nothing wrong with a law ensuring rights are protected, the issue comes from the use or abuse of it. When cases occur in which a law designed to protect people is invoked wrongly because someone doesn't like another persons decision, it causes disgruntlement. It isn't going to make someone suddenly be anti gay/Christian or whatever is relevant to the situation, but it can cause frustration and a lack of interest in understanding - which often results in glib comments that have appeared in this thread, those that made them are unlikely to be homophobes, they are simply frustrated.
In the case of the B&B couple, that is discrimination and without a doubt they were justly pulled up for it.
In the case of the Cake seller, as mentioned, we cannot be sure what truly happened, but based on the details it suggests the Bakers had no issue serving the gay couple, their issue was with the design of a cake - and simply because of the content of the design the situation was escalated.
Had it been any number of other designs which the Bakers were uncomfortable with then nothing would have happened because it wouldn't be considered discrimination, yet because of laws put in place to actually protect against genuine discrimination, this situation has occurred.
Now, one can presume there is more to the story, certainly wouldn't surprise me - I have very little time for Christians with such dated and in my opinion, wrong beliefs, so it could well be that what happened was totally justified. But based on what little we know, I personally just feel what happened is not right - and frankly it pains me to be siding with people who still have the views those Christians had.