When I think of things I want less of in my online life, Captcha's is pretty high up there! It would annoy the shit out of me to have to do it for every post. 
Unfortunately everyone has to pay the price for the acts of spammers and bots.
If we calculate all the time spent by people filling the captcha all over the world, it is a useless waste of a lot of precious time. I would also want less of it but this is not possible as webmasters and admins have to protect their web properties from spammers. May be we can have some better alternative in future.