Fwiw, I think it may have something to do with banks repositioning their balance sheets with certain types of assets (in the form of credit lines to more reliable borrowers) that don’t necessarily need to produce income to have the desired effect on the balance sheet.
I’ve taken advantage of numerous 0%, no fee offers.
The bank is simply wagering that you’ll flub up with a late payment, at which time the rate will skyrocket to 29 or 38% and the loan will become hugely profitable for them.
Their strategy never worked with me.