What examples do you have? So far I can think of Steem coin and Dogecoin. The former has the vendor lock-in issue, and the latter has no standardized automation of tipping.
Flattr was probably the most famous. It's still running, last I checked anyway. Readability.com tried something like that as well - remove ads from a site and pay the site owner directly instead. Site owners got very angry about this and it stopped that pretty quickly.
I admit that I would hate to see Flattr become a monopolistic payment platform that knows everything abou the websites you visit... but which also seemed inevitable as they have to determine how much to pay to whom ?
The biggest thing is you don't have to contribute actual money. Instead of watching the website's intrusive, tracker-ridden ads, you're receiving custom ones from Brave tailored to you based on a local machine learning profile. You're watching ads on your own, separate from the ad networks used by the websites, and so you get a virtual token that can be sent to creators you like. They can convert it to actual cash (you can too if you want).
The whole point is no money is invoked for the browser user unless they want to go to the frog me of withdrawing the bat they earned. Instead they can just assign it to someone they support
That's what's superior. Real money services require someone to pay real money.
This system could be done without the coin but I bet it would be more difficult to arrange transfer to each browser user.
As with all of these systems, where it's likely to fall down is that the monetary amount you receive for viewing ads will be so miniscule as to be inconsequential.
