There's a good argument that the time scale involved in getting a new channel isn't really a custodial arrangement. That's akin to claiming a money exchange booth is also a custodian because they physically have your money for a minute or two while they count out the foreign currency they're about to give you.

Very different circumstances to something like Wallet of Satoshi, who has had full control of the $5 I've had on my WoS wallet for the last few months.