Do you think, if you associate yourself with an Autism group (meaning that you think that you have, or was diagnosed with ASD) you tend to "throw" all your thoughts, behaviors and feelings into this "Autism basket"?
Nah.
Do you tend to think that majority of you feelings, behaviors, your perception have everything to do with Autism? Or do you separate all the "normal" characteristics and "autistic" characteristics?
I usually get more caught up in carefully monitoring my human and animal characteristics since most people get a little spooked when your growl or hiss at them when they try to pull your ear.

And I didn't particularly enjoy my inner squirrel biting a pecan shell in two without warning...
But, I am me. The only time I really get concerned about any behaviour is if it's an indication of something being wrong, like any of the stuff associated with stroke, injury, and such.
Is it intentional denial of sameness or we're just incapable of seeing it?
Not in my case. I just can't find somebody "same" enough to be worth socializing in person with!
So I'm not sure... humans do it instinctively but is it working for us? Do we really need this separation?
I do. If somebody enjoys shooting puppies and drowning kittens, I don't want to be associated with them, and I think they do need to be separated from the rest of society before they start wanting to do it to people. I wish I could say I was exaggerating, but I know a family who has happily drowned a family of cats and shot their daughter's puppy, and then bragged about all of it to me. Might say it's an Aspie justice complex, but even allistic folk I've talked to agree those people are a problem.
Morality aside, I'm just not as clingy as most people. Some people act as if they're afraid to be alone or are incapable of entertaining themselves, and I find them exhausting because they're so needy. I honestly don't understand why the self-sufficient loners come under fire constantly in commercials, media, and those ridiculous corporate videos, but those who can't wipe their own butt without an audience and handshake are considered the well-balanced and capable ones.
What do you think?
To each their own. Let the social butterflies and extroverts plan every last minute of their day to be together, let us hermits happily meet once every five years for a quick cup of tea, and let those in the middle meet as they please.