system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Is picking and eating the contents of your nostril genetic? Also, is there a reason "we" do this?

I'm 27 years old and I think I've reasonably hidden this from my partner of 6 years. We have a 1 year old and a 3 year old. Our 3 year old also openly picks her nose and eats it, and continues to despite us chastising her every time she does. 

I know I enjoy it because it's salty and helps unblock my nose. I also hold most likely misinformation that it boosts your immune system. I've been doing this as long as I can remember (childhood).

This isn't something you can generally ask people, so throwaway obviously but a genuine question and any information appreciated.
gpt
I suspect this behavior is quite common, and that it's similar to when animals lick to groom themselves.    Eating boogers could provide information as to whether one is sick, or perhaps help avoid leaving that information for predators.