My impression is that they are no longer in vogue - for a few years when I was in college (2004-ish) they were all over the place. Our industry is extremely faddish, even when it comes to interviewing...
You can still see them in some places I believe. I've heard anecdotally that Microsoft is still a fan of them.
When I was trained as an interviewer at Microsoft (circa 2006), they explicitly warned people against asking questions like that (and had been doing so for some time). There may be older employees who stubbornly persist, though.
I should add that my personal experience contrasts with yours - I did a lot of interviews around 2004 and got asked riddle-type questions by one, maybe two, people. My memory is that they mostly died with the original dot-com boom.
You can still see them in some places I believe. I've heard anecdotally that Microsoft is still a fan of them.