the recipient is EXPLICITLY saying "zap me on these mints" -- so this point is kinda moot

right now the vast majority of nostr users are on either alby, WoS or primal (myself included)

with this, instead of having a couple of huge custodians you can disintermediate that market and have and use, at the same time, 5, 10 custodians

you can and should sweep the balances from the WoS of the world into whatever you have.

There are many people running small LN nodes that are not being used as their zapper because running a zap-capable LN nodes is much more involved than running just an LN node.

With this you could literally just use the custodians while you are offline and the moment you come online sweep everything to your own LN node.