The problem I see is that someone might assume that since their first step was free (custodial without fees) it will always be like that. And of course you can try to educate later on why self-custodial has a price, but generally people are so used to free stuff that most likely they'll expect it just by laziness and feeling of entitlement. And they might treat the custodial solution as something good enought to keep bigger sums. I don't want to have bad feeling on my conscious later if that gets rug pulled.
Discussion
For example, nostr:npub14wxtsrj7g2jugh70pfkzjln43vgn4p7655pgky9j9w9d75u465pqvagcye adviced bar baazar to install bluewallet lightning custodial.
I image when he realized that people using the custodial LN were advised to move their funds out because they'll close it and it was past the deadline the feeling that you advised someone and now they might loose money because of you is something I don't ever want to feel.
Luckyly everything turned out ok, it was not a rug pull and they payed the funds even past deadline.
But I prefer to avoid the worst possible outcome.
Self custodial education is better then just going for easy but risky solutions just for increasing adoption.
If someone is not willing to accept that education, it just means they're still not ready/needing bitcoin.
I still believe that you can not orange pill anybody, they must decide to do it themselves. You can help educate them of course and that is very precious value.
Convincing some merchant to install custodial wallet just so that you can pay them in sats does not mean you oranged pill them IMO.