alt Hacker NewsmCaptcha, ALTCHA, Cap, Friendly Captcha, Private Captcha, Procaptcha, Anubis... there are literally dozens of open source alternatives that aren't feeding the Do Be Evil company... not to mention all of the commercial alternatives - if for whatever reason, you do feel like paying for a service that costs nothing to offer
Gen off it. Fraud detection is nontrivial and requires ongoing effort. It’s reasonable for people to be compensated for that.