I think it would be discrimination if the provider was forced to provide service on a day that is closed due to religious observance.

If I don't observe Sunday as a religious holiday, does that mean I can demand the doctor open his doors on Sunday to satisfy me? Absolutely not.

My local produce store is closed on Saturday because they are 7th Day adventists. Can I demand that they remain open on Saturday? No.

Nobody should be able to demand hours of service no matter what service they provide. As long as they are available on a regular basis with regular hours, what does it matter which day(s) they choose to close