I come to the interview to get a real job not to please the smart "gotcha!" recruiter.
And part of a real job involves solving real problems. In an interview, you have a very limited time, so you have to come up with questions that test the candidate's ability to solve problems within a certain timeframe.
Another example is from my own "worst interview ever" where the guy asked me to implement a BFS and a DFS on a tree. I mentioned that I'd literally been debugging an issue with a DFS algorithm all day at $dayjob, so should be a piece of cake. I wrote out the DFS example in 10s, but then when I got to the BFS, I spaced out on how to write a for-loop. The interview literally just laughed at me, saying, "that sucks for you" so instead I simply showed him how a BFS works and his answer was, "I don't care, I want to see code."
As an interviewer, I get it. I expect you to know concepts, not be able to perform rote actions and put on a show.
Either way, if a candidate misses such a question it shouldn't be a negative. Using such a question as a filter is a bit ridiculous.