Notice that the sites they mention are mostly newspapers.<p>Print editions of newspapers are going the way of the dodo and it is not sustainable to offer full, free access to their websites so for years now they are moving to paid-for access on a subscription.<p>Here they keep offering free access but with ads or you can choose ad-free access with a paid subscription and to me it looks like this is a way to nudge people towards subscriptions ('nasty' ads and tracking or 'nice' ad-free, tracking-free experience).<p>The bottom line is that a business needs to make money.
> a choice: buy a €4.99 monthly subscription or give up your data.<p>Any reasons for them not to sell the data? Ability to pay requires to increase profile with: login, password, email, bank account and of course articles you were interesting in. This is way more data that a website can steal from user's browser.