WHAT EXACTLY IS MAC?
The acronym MAC stands for the Manhattan Association of Cabarets & Clubs. (Originally, the acronym was Manhattan Association of Cabarets, but as MAC evolved, it grew to include comedy and jazz clubs, thus adding "& Clubs" to its definition). MAC is a trade organization — designation, 501C6 — with a dues-paying membership. It is classified as not-for-profit. This should not be confused with a charity or foundation classified as a non-profit designation, 501C3. Contributions to MAC are not tax deductible as they would be to a charity. If you treat your performing/artistic career as a business for tax purposes, you may be able to deduct your membership dues as a business expense; consult your accountant.
Generally, people who give money to MAC do so with real love and support for the live performing arts, since there is no other financial benefit or "write-off" for a contribution beyond, possibly, one’s dues.