I know all too well that there are real people behind all of it. I have direct, sometimes painful experience of that.
On the other hand, I am also aware that what people do online often doesn't reflect what they are like in reality. Tge nature of the medium, anonimity and several other factors create some form of inline personality that is often quite distinct from a person's offline one. To be sure, they are the same person, but I suppose one way to look at it is that it amplifies certain aspects of their personality, and masks others.
Sometimes, this is deliberate, sometimes, it arises because there are fewer subliminal cues, such as body language, and often slower, more deliberate communication.
Besides, online much more about a person is hidden. And this can be played with.
I play up being a catgirl online. It should be quite obvious to anyone that this isn't real, but even so, the illusion holds up much better online than it ever could online.
Besides, I can easily say that's what I am online without concern.
Were I to act that way in person, or worse, try dress as though I was such a thing, people would quickly think I was very strange, or even insane.
Unless of course, I restrict it to specific environments where it doesn't seem so out of place. Like, say, an anime convention.
That perhaps is a better analogy. The Internet is like a special environment where different social norms apply.
Just like wearing cosplay at an anime convention (or halloween party) is regarded differently to just wearing such stuff randomly in public, so behaviour online is regarded as different to offline behaviour.
Remember that social norms and conventions, what's considered acceptable and what isn't, and so on is context specific, rather than universal.
What's acceptable to do with your lover is different to what you can do with family, which differs from friends, which differs from work colleagues which differs from strangers.
What's OK in a night club isn't OK in a restaurant, and neither is OK in a cinema.
Context matters a great deal.
So why should it really surprise anyone that the Internet is a context all of its own? With it's own quirks and rules. (actually it's many contexts, because it's a collection of seperate sites and programs, but the general point remains the same)