Brendan mentions in interviews that they started building on bitcoin, but the fees were too high (his words, not mine). In my opinion, I simply think they wanted to fund raise with their own token, just like most issuers of shitcoins. i agree with you - there is no need for BAT now that we have Lightning.
Bat is a security, they found a loophole tho where they can use it as money, so they wont get in trouble. This is why they will probably die on this hill. If they start using BTC or anything else instead of BAT then they are likely going to be owing the SEC alot of money for doing an unregistered security sale
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