I'm hopeful this isn't canon. Chapter 4's comments had someone I agree with, that the twins offered him a very vague and empty promise. However, someone else pointed out that they do contribute a sense of stability and friendship that he hasn't allowed himself in the decade he's been there. But...if this is really how shallow they are, on top of being more than a little annoying, then I would consider this "investment" as a massive waste of time, if I were him.