How do you monetize a robot?
Converting the effort into cash is tough, but the strategy exists.
Project HoneyPot is an API which allows any website to do this for honeypot email addresses which are injected the website, along with a ToS which says:
> By continuing to access the Website, You acknowledge and agree that each email address the Website contains has a value not less than US $50 derived from their relative secrecy.[1]
This guy[1] apparently spent years just suing email spammers and occasionally winning.