I don't hate Christians. I don't care much for bigots, though.
The only bigotry I see is being aimed at someone who has specific deep beliefs related to their relationship with their deity.
The baker had served gay people in the shop before, as I am led to understand, so it wasn't a bigotry against gays.
However, the idea that two people in a same sex union is the equivalent of the sacrament of Holy Matrimony, doesn't make the grade with Bible believing Christians, and to create a wedding cake for such an event to celebrate it doesn't either.
No bigotry, just a desire to NOT create something, based on a deeply held religious belief.