Although if they are considering multiple PhD maybe they dont have to work, they could be independently wealthy.
Anyway, I think in some ways your point is well made, even if its a country other than my own, which I have discovered really does not rate academic performance and in which is very, very easy to fall into this "over qualified" bullshit trap, there's a hell of a lot of people in medium to large firms who "worked up from the bottom" or took non-academic routes to their positions and are straight up bitter about others learning.
Which I think is stupid, given that for the most part it just means people have been well read at one time in one particular area or discipline, I know there's skills involved too but I think it boils down to that. I wish there were more smart people but I also wish there was such hang ups about smartness too.
I'd say to Warrior that as important as his core topic is, and he would want to study something that's interesting because I did a masters and I almost hated my choosen topic/area of research by the end of it and it was just a literature review thesis, not what I imagine a research project in a PhD could involve, to consider the extra curriculars and other aspects, as simple as accomodation for instance.
Sometimes I think that a decent array of extra curriculars which can evidence your relationships with others a bit more can counter the whole "over qualified" thing or sometimes it doesnt mean shit and they have internal candidates and what not, study something because you want to do that for a few years.