"How are they predatory? Users know exactly what they are doing? Can we stop pretending that nobody has agency and is in control of their own actions?" .
I agree in that users SHOULD know what they're getting into, but financial literacy is not as wide spread as we'd like. There are a lot of idiots out there which these companies know will be their primary customer base, which is what gets them labeled as predatory. Personally, I have no sympathy for either side because the layman who falls in that trap always has the freedom to default on their agreement if they also accept the consequences (eg lower credit rating). The interest calculated by the lender factors in the rate of defaults, so you know they're raking it in until enough customers collectively refuse to pay.