My darling husband has done this now with BOTH of my babies.
I can only assume it's his way of making absolutely sure that our child is, in fact, hungry.
Hold hungry baby up to face.
Let baby root around trying to find food.
Let hungry baby find and violently suck on nose for 30 seconds.
Yell at wife to come feed the baby.
She's hungry and slightly pissed.
He gets this look a lot around here.