I believe there is a legitimate purpose for tonsils, relating to the immune system. Tonsils are not removed anywhere near as often as they used to be, from my understanding. You might have suggested the appendix as a better example. As for the appendix, well, you got me there. But just because we might not be aware of the purpose of tonsils or the appendix, doesn't mean they don't have a purpose. I'm sure nobody knew what lymph glands did 200 years ago, but that doesn't change the fact that lymph nodes serve a purpose.