Replacing ads with their own ads, running a cryptocurrency within the browser. I don't want microtransactions to view sites which I feel like is what Brave is hoping for in the future. I mean, microtransactions are the name of the game in cryptocurrency but doing so for online content is especially egregious.
When able to do so, many choose products based on principles regardless of how they use them specifically (hypocrisy and comparison of evils notwithstanding).