Are there any examples of this being done?
Ad companies generally don't. Data brokers will set user data, but advertisement based companies do not sell user data.
> does that make Google respect user privacy a lot better than other ad companies?
"better" is the operative word in that statement. Just because Google spies on me and is slightly less worse about how they use that data, does not mean that they respect my privacy.
I mean, I haven't audited their systems and haven't seen any reports from independent auditors, but at least they are making direct statements about privacy that the other ad networks aren't.
And iirc they have stopped doing that with the browser also.