You will always encounter people who will use you secretly for their benefit, and they are not even aware that you already know what they're trying to do and why they want to be close friends with you. 

You have a choice to just completely shut them out off your life.

But you choose to feed their egos because you understand their need for it.

Sometimes it's just really sad to see people try so hard to get recognized, to the point where they lie about themselves to others, and you're one of the few who can tell.