I used to see such colleagues as fake friends too. Now I see them as just protecting their rice bowl. If so happen the boss wanna socialise with them it’s also hard for them to reject right. As long as they don’t do something outright harmful, fakeness is part of working life. What should be called out is those who are not only fake but manipulate others to harm your career, all to protect theirs. But too bad, even if you try to call this category of people out, you may not be believed.