Cook's Law

"The Decline of any Organisation begins with the appointment of the first Human Resources person"

....because that means that the founders have delegated an essential function to someone with no stake in the outcome.

Speaking as a guy who interviews people that third question [Jokers] is highly relevant if asked by the team the person will be working with instead of the initial HR person as it's indicative of how well they will mesh with the team and how they think. In real life personality matter and having a black panther and a KKK member on the same team doesn't end with two highly productive workers nor does hiring somebody who despises unions into a low level union job gig. The real challenge, given obnoxious discrimination laws, is getting folk to answer the question honestly or making sure the questions you ask don't run afoul of some policy. Nothing worse that hiring a person only to find out oil and water.

As for the world hunger question, I love asking questions like that also (and hell, might even use it now). Not because there is a right or wrong answer (I'm indifferent how you choose to answer it though your answer might lead to more branching questions) but it shows how you think. If you can't methodically come up with an answer (even if wrong IMO) or answer at all (i.e. you just perm freeze) then I don't need you in a technical position give you inability to troubleshoot.

The only real problem is when the interviewer expects the interviewee to confirm the interviewers biases / world view on these questions (i.e. gotcha questions). To try and avoid this I make a consciousnesses effort to focus on the the process, not the actual belief, i.e. when I say "your answer wont' be used against you" I truly do mean it short of, as I said, a non-answer/freeze.

"[...] Human Resources [...] neither are they human nor are they resources." -- Mike Williams from Ericsson (IIRC)

I was part of the "stupid oddball questions" chorus before I actually started preparing for my Google interviews. Lo and behold, after some quality time with an algorithms book (never studied CS), most[0] of the questions I had thought stupid puzzles unrelated to software turned out to have straight up solutions that jumped at you if the basics of sorting, searching and data structures were on your mind, and as such seem quite relevant to identifying candidates that had not only studied these things out of a book, but were also able to apply them to real world problems.

The hourglasses are a great example - if you're smart and think algorithms, the state space and search tree jump out at you and enable you to find an answer, then generalize to finding all times you could possibly measure with this set of hour glasses, then any combination of hour glasses, how long that would take and so on.

My actual (engineering) interviews were quite straightforward software questions btw, with the potential exception of one aside that was about a concretized variant of the halting problem.

Eagerly waiting for part 2 and part 3 then.

[0] I still fail to see the point of the monopoly thing, and there are a few other questions that are just stupid, but most of the time when I hear dumb examples, they're from the forbidden list.

So how do to people managment and hire people then while I agree with everything you wrote?