Other people's children

Why is it that people with small children automatically assume that everyone thinks their little darling is adorable? I'm in an elevator the other day, on my way to the office, lady & toddler get in. As I'm about to select my floor, she says: "No wait - he likes to do that - it's his thing" Who cares? I'm on my way to work, contributing to the economy that ultimately has to provide a future for junior - that's my thing!