Because in sociology there is such a term as social role. And the social role follows from certain requirements of society to the owner of this or that social status. It is natural for a person to behave differently with their parents and friends. Or with your child and in the company of fans at a football match. Moreover, it is quite normal when a person with one friend will drink and discuss memes, play basketball with a healthy lifestyle friend and eat healthy food, without even thinking about McDonald's, and discuss anime and play computer games with another person. Because his friends have different interests and hobbies, it would be stupid and selfish to impose sports on a computer lover who will not reach 100 meters, and drag a healthy lifestyle into a Mac, tormenting him with food that he may very much like
As for me, a person has many images, and it is up to him how to be with this or that person. It is impossible to treat everyone equally, if only for the reason that everyone acts more often according to the principle "treat people the way you want to treat you" ...
It seems to me that this is due to the fact that most of these people are just clones who want to match their, as they believe, a bunch of people. Although, in fact, this very group does not take such people seriously. Ask why? Yes, because they are like copies of a certain person, they do not have something that can hook, attract and interest in themselves. They just imitate the idol who wanted to spit on them. Yes Yes. Exactly do not care, because he is disgusted to see such inadequacies who do not have their own personal life.