Those "stupid programming puzzles" are about evaluating problem-solving abilities. Asking about architecting a system from a higher level also does this. Asking how a browser works is in the memorization category, and I just don't understand how that can give you useful information.

Now you didn't give a lot of details - maybe you're upset about being asked to implement mergesort. That would also be an exercise in memorization. I'm not condoning that.

Being able to analyze an algorithm from a time/space complexity standpoint is about whether you can reason about code. I think that is also a useful thing to find out in an interview.