No it isn't. The pools are allowing anyone who pleases to use their facilities. What they aren't allowing is anyone to use their facilities for religious purposes. The Muslim women are using the facilities to swim, not to practice their religion. The Christian group was using a pool to practice their religion. Whether you agree with the separation of church and state or not, I don't think you can say there's a double standard here.
Where is the difference in PRACTICING religion and OBEYING it?
They rented that pool because they had to follow the strict laws of their death-cult. They had to obey the rules of their lords and masters. And who paid for it? The HUSBANDS! The abusers.
If renting space to an abusive 'religion' that helps enforce their brutal rules for their women isn't participating in that religion I don't know what is.
Clearly you disagree, but I believe there is a double standard. Why do they want to have a private swim time? It's not simply to avoid crowds...it's to maintain a level of modesty that they see as dictated by their religion. They are having a private swim time to observe their religious tenants...the same as the Christians, although I think the Christians would be willing to do it at public time but wanted the private time to avoid causing issues with anyone who didn't want to observe the religious practice. Again, I don't have a problem with them renting the pool, but the separation of church and state thing is so poorly interpreted that we might as well burn the rest of the constitution as well thanks to the flaky judges we've had and their rulings. But my point is, they are both observing behavior directly related to their religious tenants.