I mean sometimes they do know, they’re individuals after all with varying levels of knowledge and experience. If they say they don’t know I thank them and move on, but plenty of times they’ve been able to answer my questions. Seems a bit patronizing to assume that just because they work at a store like that it means they don’t know anything and can’t answer questions. I actually literally asked an employee a question about a plumbing fixture in a big box store recently and, shocker, they were knowledgeable and had the answer to my question.