I read NIP-57 just now.

I guess what confused me is I've used Nostr clients where everyone has a Zap button. Who is holding onto those lighting receive addresses until they specify where they want the funds to go?

Like if someone Zaps me right now, I haven't specified a place for those Zaps to go. Do I call the Damus staff and they send the total of the micropayments Zapped to me over Nostr to a Bitcoin receive address? I don't think anyone has Zapped me, I'm just trying to wrap my mind around how it works since I was wrong earlier.

Maybe I need to set aside an afternoon and read about how Lighting works, perhaps I just don't get that protocol.