My question involves civil rights in the State of: New York

My question is in several parts, I will only get to the main points. At the root of the matter is a religious based group who is classified as a 501(c) (3) charity with chapters nationwide. Are they legally allowed to restrict attendance on the basis of age? The group’s target audience no longer considers me a person they cater to since I passed an age threshold. However, my situation and attendance is far from isolated. The group’s main function is a service they conduct (open to all faiths) that includes socialization, dinner and prayer to a group of people in return for voluntary contributions. The meetings are on the grounds of a church of the same religion, but the group is not a ministry of the church. Their affiliation as far as I can tell is limited to the generosity of the pastor allowing the space to be utilized for their event. I can’t seem to find a conclusive answer from any online resource.

Assuming they are allowed, would I have a case if asked to leave because I am not in the desired age range AND I could prove other members in the same age group as I am regularly attended without interference from the volunteers who conduct the activities of the organization? This would most likely be the focus of any legal battle (skirmish actually). My feeling is that since some personal friction arose with a small percentage of the tight knit group, they may use my age to further harass me.

Lastly, if I was able to win the right to return (several steps into a scenario that has yet to occur), could I ask for reimbursement of legal expenses incurred?

I realize that anyone analyzing this situation would need more information, but any help or input would be greatly appreciated. This includes directing me to websites to research this subject on my own. Please let me know what additional information I can provide.