My point is that you don't know his situation, so you can't judge his actions. You don't know how many "externalities" there are (whatever an "externality" is).

The fact that you can't imagine a worthy justification (in terms of his value system or your own) doesn't mean that one doesn't exist. And no, you cannot categorically deny the existence thereof.

You seem to be judging people's decisions based on your own value system and dreams as opposed to theirs.