@Gyarurun and Facebook for me is a way to stay in touch with relatives and old friends. A lot of other people use Facebook to virtue signal in their echo chambers and harass each other online for having different opinions. Some people use Instagram like you to stay connected with a small group of friends. A lot of others, like what was demonstrated by the chapter, work hard to fake better lives then they have in order to to show off to other people.
Don't take things so personally. If it doesn't apply to you then who cares? If it does then learn to laugh about it or change it. I'm sure there are several things that I do that others would point out as incorrect social behavior like reading manga for free on this site. Reading comics is an immature thing to do after all and piracy is morally wrong. But it gives me enjoyment and I don't try to mischaracterize it as something it is not.