These places give you mbtc for payment whihch would take you 1000 claims in order to get 0.001btc
No worth it to do these micro earning tasks.
i believe that many are doing it with a bot and not manually, a coder can simply make a bot in no type in php and resolve captcha with it, simple and easy
there are also some that use bot for signature campaign(using Xrunner i think), i see at least one spamming 120 post then he cancelled everything in few seconds when i caught him with a quote