Lutheran Settlement House interview questions

Two rounds of interviews, very personable staff, asked great questions. Helpful in getting to know the atmosphere of the non profit. Very professional. I was glad to get an offer from them.

Applied online, had phone screening conversation, then was invited for in-person interview at their offices. Friendly and laid-back interview process. Asked about my experience, work history, goals with their organization. Total process took about 2 weeks. Terrible terrible part -- after I went through the interview process and received a call to offer me this position, I asked to speak with them in more detail about particulars - salary, benefits, starting dates ( I had mentioned to them I would need to give two weeks at my current employment prior to starting). Out of nowhere (and after 2 week interview process) they told me this was an unpaid position? Why would anyone put a job offer online (with a tag that said 'our organization offers competitive salaries and benefits') and not mention that clearly and upfront? Why would you expect someone to be a program manager for free?! Wouldn't you find that odd when I was talking about quitting my current employment for this opportunity? Super bizarre all around.