That's not selfish - we only have so much time. The expectation that one should engage with everybody all the time will lead to misery. It's totally okay to say

That's not selfish - we only have so much time. The expectation that one should engage with everybody all the time will lead to misery. It's totally okay to say " no thanks, have a nice day" Edit: I realize your pointing out the prudence of an upfront decision of whether or not to engage means we probably agree here, I just consider the word selfish to be a bit harsh