Why is it that some popular "cool" kids are like this after graduating highschool?

Why is it that long after highschool, some popular "cool" kids like eccentric introverts and try to make friends with eccentric introverts while at the same time, ignore, are condescending, and are rude to normal average kids even though those normal average kids gave those popular "cool" kids attention in highschool while the eccentric introverts never did?
Why is it that some popular "cool" kids are like this after graduating highschool?
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