Well between girls who are really bff it sometimes happens... but then it's just more like an extended kiss on the cheek.
As someone who has moved about in the world, my experience is the only people who greet each other with a kiss on the mouth, are those who are in an intimate relationship/married. That goes for the whole world. For everyone else there are varying degrees of local costums and practices, some which involve kiss on 1 or 2 cheeks, and some don't even touch.
I think it's funny. I laugh every time
I think its when they just start out, and hardly intimate, it wouldn't be natural for them to be greeting each other with a kiss. That comes with a more established relationship (with or without sex). I think that's what the initial issue was about, and frankly, I too have grown tired of the "that's the way they do it in the West" myth.
Im also talking about other mangas. In this manga it was like i may be born in california bug dont worry im not gay. And i think the dude thought they kiss as a greeting or something. Iv seen alot of mangas that say its greeting in shoujo mangas as well. But kissing a guy or girl on the lips isnt a greeting they sometimes do it to their kids or cousins or something.
It really pisses me off when mangas are like kissing is a greeting in foreign countries im like no bitch