I just dug up info on how Brave’s contributions thing works and it feels like such a mess. According to https://brave.com/publishers/ - once you have accumulated $100 in contributions they email “the webmaster at your site” and the owner of your domain according to the WHOIS. I assume this is “webmaster@domain.name”, which I sure don’t have set up on my personal site. - you have to “check your balance frequently and…
It's been a while since I started using Brave but I felt they were pretty up front with how the payments worked. I do understand the frustration though of those who don't see this. Brave could warn visitors donating when the content owner hasn't set up Brave Payments. Brave could refund said money back to the visitor if it goes unclaimed after a while. Just random ideas from someone who actually likes their attempt.
Even more workable is to be opt-in only. That's what I would do (to the point that I developed a protocol that's purely opt-in).