Did that actually work? I just assumed they would find a way to charge me 'interest' by having processing fees or some other scam, so I never used them.
It's much less effort to use my everything credit card and get my 2% discount than to do a 0% apr over four months (or whatever), setup a new account, setup payment at that new account, remember to make the payments, etc and for what? Short term bank interest on most of my purchases would be peanuts, especially since I wasn't getting 2% bank interest when BNPL was at 0%.
I imagine the BNPL people made their money from the same kind of CC fee models and from customers who ended up not being able to stay within the 0% timeline. From my memory it usually had some big fines or interest rates if you couldn't make the payments.