Again, you don't see tons or even ounces of people wanting to deny service in point of sale things. Why fight for it if no one really wants it?
Because, despite your dismissing the point as "absolutist", the law operates on precedent and principles. If we allow government the power to ban biases that the current majority doesn't like, another majority will come along with a different agenda and different biases to ban. The Alex Jones dust-up is a great example.