I have to disagree. Just a few weeks ago I saw a mid-30 year old woman out on her bachelorette party night with a dozen or so friends. They were all kissing each other.
This is absolutely the norm for parties at present. You don't see this type of activity at every party with lots of drinking or in every bar, but it certainly happens enough so that one could not consider it unusual behavior. We know why girls do it.
And this isn't a new thing, either. Such activity has become more common over the last few years, but I've seen it happen at parties since the late 90's when I was in college. Attend any kind of lively frat party, and there will be girls kissing. It just goes without saying, in the same way that you know you'll find beer there.
KC falls into the classic demographic for that stuff - she's single, likes to drink & party, and has a wild side. This isn't something girls necessarily "grow out of" by the time they're out of high school. In fact, I'll bet my bottom dollar that it is more common among older girls - such as those who are college age. As wild girls get older, they tend to get even more adventurous and lose even more inhibition.... up until the point when they finally settle down (that is if they ever settle down).
-edit
I just wanted to add that there is another activity that is now "normal" among girls. The practice known as "sexting", or sending naked pics of themselves. I think there's a general perception that this is something of a high school problem, but it isn't. College girls do it to, as do women into their 20's and 30's. The older women just tend to do it more via chat than they do via cell phones, because they have more privacy when they use a computer.
It is for this very reason that I would not be at all surprised to find out that there are far more obscene pics of KC than what the public has seen so far. Many girls her age have them.
