Hi SmartChic,
I agree - it's a problem and has been for many years, not just on this forum, but many forums I'm a part of. Sometimes people have issues with the search function, though, which was a huge issue before we changed over to vBulletin.
I will put a sticky at the top about using the search function before asking questions; however, I'm not sure if it will help because it seems that many people don't bother with the stickies either.
I'm not sure deleting them is the answer, but I think we could possibly merge those types of posts into other threads.