I don't see anything inherently wrong with it, probably not only because of my education and experience, but because I was raised in a somewhat "kissy-touchy" family (even though oddly enough, I'm one of the more reserved in the family when it comes to spontaneous hugs, rough-housing, etc).
I have a bachelor's degree and masters degree in psychology and in my jobs had a lot of training in cultural differences when it comes to things like personal space and physical contact. I've also always had an interest in cultural, subcultural, ethnocentric, and regional differences in etiquette and taboos.
As a result, I try to be very aware of people's "comfort level" because not everyone likes being touched. And on the other hand, some people won't trust someone who is too stand-offish by their own cultural definitions (we learned a lot about that when I was in law-enforcement. Because in some cultures, when a person is trying to be respectful or apologetic, they get closer and closer to the other person, yet to most (in the USA) it's a violation of personal space and often is perceived as a threat).
In some cultures, it's not uncommon to kiss even strangers in greeting, even men kissing other men, even strangers on the lips as a greeting. Even in the USA, there are regional, social, ethnocentric, and individual differences, so "normal" and "appropriate" are relative terms.
Propriety and etiquette are in the eye of the beholder, and because there can be so many different perspectives, even within a majority culture, I think it makes more sense to assume the best, BUT communicate your own preferences. If someone does something you are incomfortable with, or you would like them to change, communicate it - ideally without blame or accusation. If the person doesn't respect YOUR preferences, and doesn't try to accomodate you, you may have to get more assertive about it, but you don't have to start out assuming the person's intent is disrespectful.