I think you didn't read our FAQ or other site docs, and just assumed the worst. Why is that?
How do you pay publishers on sites that aren't partnered with you?
8. How do you use Bitcoin (BTC)?
We’re still developing the system, now entirely in the open source on github.com, but at this point we know we will use BTC only for permissionless payment delivery to user and publisher wallets that we will create using BitGo’s APIs. We hope to keep funds in BTC only in monthly payment buffers, to reduce effects of volatility. We intend to let expert users “bring their own BTC” to self-fund their wallets and auto-micropay for as much of their browsing as they like.
See also https://www.brave.com/blogpost_2.html which discusses user and publisher wallets. We'll have more in a week or two on the Brave Ledger payment system.