I didn’t know how they were doing it and you are correct about custodial being a downside. A big one.
Discussion
Custodial is actually more common than not for a zap wallet, as running Lightning is nontrivial. Being KYC is the bigger issue.
It goes with being an onramp so more power to that mission. But if you know enough to be asking the questions you probably know enough to go with another option, too.
Didnt know Strike was on the backend. Love them as an exchange. I'd just as soon keep my exchange and my zaps separate.