I suppose. I can't remember now, exactly, but there was something I did a while back that required a series of captcha answers to get through and it was just plain annoying.
We're agreeing though that something that allows humans to differentiate from bots is a good thing. :) I'd prefer not having to do anything else because I'm the human and don't feel like I'm the one who has to prove I'm human, even if it is a simple and easy, fraction of a second box tick. :)