> but for a browser company, isn't a browser extension better than some other way to opt out? otherwise they would have to associate you to an account.

Well the better way would have been to honour the browsers 'Do Not Track' headers, but Google pretty much ignored these, presumably because it would have caused too much impact, which is one of the reasons it failed.

But now, Google could support 'Global Privacy Control' by implementing it in Chrome and honouring GPC headers across Google! That's the obvious way to support an opt-out considering there is an emerging standard and that they own a browser. But... again, it's probably better for them to ignore this from a commercial perspective and in their best interests if GPC fails, so better to implement some shitty add-in that discourages people from opting out (if you want to opt out of tracking from 100 companies, are you expected to have 100 different plugins?).