He is useful, since he acts as a living proof that

A) I have bitcoins, since I can just throw them away at will

B) He has yet to realize, what I say here is true, and anyone who reads it can just buy bitcoins with his spare cash and be rich, no need to beg to have them.

The most juicy early adoptership window is right now, and it closes, when 2% of the world's population has bought in. At that point we will be at $300/mBTC, my tip to this guy could have bought him 10 houses [NOTE: I kindly asked him to give it back, since it was just the proof anyway - he can invest his own money and be happier LOL], and we are entering in a dangerous bubble territory. Buy now, or refrain from buying above $300k, like I refrained from buying bitcoins during its runup and crash in 2011.