Why is a stupid answer to a stupider question a violation?

If someone asks a question that makes absolutely no sense in a particular category, and you make a dumb answer, that doesn't relate to the question, but does relate to the category, why should your answer be a violation if the stupid question in the wrong category is allowed to stand? The dumb answer only points out irrationality of the question, but I suspect the concept is beyond the comprehension of some people. Comments? Has anybody else experienced this?