I think "supplier" would've been a more accurate term when bank accounts actually paid interest. Savings accounts at my bank pay 0.01%; standard CD rates top out at 0.05% for a 1-year.
(I do have a high-yield online-only savings account that pays significantly more than that, and feel like I'm much more of a supplier to them, although in some way "supplier" connotes that I'm actively doing work to provide a product or service for them, which I don't feel toward my bank. But the article is about retail banks; the bargain with most retail banks these days is "They give you convenience; you give them money, which they can loan out to make more money." That's much more like the bargain that Internet companies and TV make than the one that say AdSense, App Developers, and Uber make.)
(I do have a high-yield online-only savings account that pays significantly more than that, and feel like I'm much more of a supplier to them, although in some way "supplier" connotes that I'm actively doing work to provide a product or service for them, which I don't feel toward my bank. But the article is about retail banks; the bargain with most retail banks these days is "They give you convenience; you give them money, which they can loan out to make more money." That's much more like the bargain that Internet companies and TV make than the one that say AdSense, App Developers, and Uber make.)