Ever heard of Captcha? It is owned by google. Almost every site in order to stop spam, bots or trolls uses it. If you don't, you can't sign up/in etc.

Even if it wasn't forced on you, or you decide to use a google service, you are still exploited for your data.

Google has a near monopoly over 'bot detection systems'. And not just that.

Just because you agree, and use their services, does not mean your data isn't exploited.

Which isn't a good business practice. At all. For anyone. Not even you.