As with job promotions, and politics, this isn't any different. What is a promotion? What is being accepted into any group? It's a GROUP of PEOPLE, that DECIDE WHO gets it. So, by that logic, obviously because of human nature there is going to be favoritism and who they are COMFORTABLE with. Generally, yes, it's a lot of ass-kissing and A LOT of favoritism. Certain people may still deserve those promotions, sure. HOWEVER, the PEOPLE WHO DECIDE seem to neglect that just because you LIKE them, doesn't mean they are SUITABLE to handle more responsibility.
Basically, just because someone does the POPULAR thing, doesn't mean it's the RIGHT thing.