person A: I saw a grown woman pick her nose and eat it earlier. 
person B: Okay_comma_ so I never understood why people ate it. What is it about it that makes them want to do that? I just flicked mine. And I thought it stopped at a child's age. Really interesting.
person A: I was so grossed out by it.  I think it has to be a oral fixation or something like that.
person B: I've heard of oral fixations before_comma_ but only in the context of like chewing fingernails and smoking cigarettes_comma_ etc. But I guess if I think about it_comma_ a lot of people chew fingernails_comma_ and I'm sure that's just as bad bacteria-wise. Maybe the booger eaters are on to something.
person A: Maybe it helps build their immune system.