Staff meet and greet

So I had a phone interview early this week for a unit manager position. I think it went really well and they have asked me to come in to the facility. The first hour I will be there will be a meet and greet with the staff over pizza, and thenI will have the formal interview. This will be my first experience interviewing for a manager position and I am really excited.

I'm wondering what I should be asking the staff. In addition to them meeting me, I think it's important for me to meet them. Has anybody done something like this before? How do these meetings normally go?