I don't think they can.
The whole confirmation code reading is extremely tricky, there are a few harvest bots (illegal spamming etc) that bypass about 80% of the verification words but, since they are illegal, they aren't integrated in standard program plus you'll get ip banned pretty quickly so you'd have to hop proxies.
End of it all it might be just as much work
, so if you're broke or cheap (like me lol) and can't afford a payed account I think you're stuck with confirming manually.