Exactly. 95% + of the work out there is more about plumbing and a doesn't design to plumb together. On the rare occasion when I have had anything algorithimc to do I Google for similar problems.

The last time I had a proper algorithmic problem, I was in an academic institute and we had a guy researching algorithms so I asked him (though he didn't come up with mush). It was basically a variation the stable roommates problem. I came up with a solution - brute force plus a load of optimization and it worked well enough for the purpose.

When I get that crap in interviews some of the time I get the answer, some of the time I don't. Its pot luck. Its says very little about my skill for the jobs I am applying for. Ironically I was way better at answering those things 15 years ago when I was fairly crap at building reliable robust systems.