It's most stark when you later see them interacting with people who they consider to be their actual friends / normal people. Suddenly you realise the interactions you had with them which at the time seemed positive were actually them talking down to you, humouring you, placting you, and being polite.

Despite numerous prior interactions with these people, you now realise that you were always kept at arm's length and never even stood a chance at getting to know the real version of them because it was never shown to you. It was withheld from you because they don't consider you their equal. To them, a real connection with you could never exist any more than could a real connection with a child. They speak to you on what they consider to be 'your level'. Patronising you.