I voted no, because you still have to actually play the game...
That being said, I usually don't use them unless it's a game I really care about and want to get all of the extras - usually I can get to the end of the game without it. But if I can't, I'll get the guide and figure it out from that, and I don't feel the least bit guilty about it. I want to have fun playing a game, not get so stressed out I can't enjoy it while I'm trying to figure out what I'm doing wrong.
I think there are some times you almost have to have it. Reminds me of that great line in Toy Story 2: "They make it so you can't beat the game unless you buy this book - it's extortion!"