Not a subject people both familiar and not, I grew up with ever talked about. Relatives greeted kids so. Maybe we kids didn't notice what adults were doing because why would that matter? Youth cultures didn't greet beyond using hand and arm touching. Ex-lovers? ... whatever, that's their business.
But the whole hug thing goes deeper because we are really discussing body touching between people and especially between the two genders.
As a matter of being friendly with single women acquaintances, I like when they want by their own choice to smile with friendly eyes, moving nearer to my head, close enough to even hold my hand or upon greeting me do so with a hug that shows they are comfortable being around and hanging out at that trusting level. As a small thin peaceful male, I'm by nature somewhat less naturally concerning to new acquaintance women hanging out around me, that maybe choose to get closer to me, without having to worry about some unintended social emotional reaction.
Likewise, walking urban streets, crossing paths with the many dog walkers, most dogs at first glance must categorize small thin me as maybe just a non-threatening huggable kid. But then close up dog think I'm maybe an old frail man haha, so yeah all those friendly dogs love and want to hug mr dave to. Well, at least join him in a friendly puppy style sleeping pile.