I am a little suprised to find google captchas on this site. Especially as it is a site about FOSS. It is just another of their tracking mechanisms in a somewhat useful form. And it is not practical, either: maybe because I am using a VPN I have to enter a captcha on every message.
As a question:
Is/has spam (been) such a big problem on this site, that is necessary to give personal information about your visitors to Google?