The point is that if they're stretching payments over multiple weeks/months then they can't afford it.
You might say that buying a house on credit isn't frivolous but a pair of shoes on credit is, but where do you draw the line in the middle?
(Disclaimer: I work at Square, but I am otherwise completely uninvolved with this acquisition or product area.)
Car loans and Houses have a very controlled lending market. Even more so with business loans.
I think there is big difference between monthly payments for a Go Pro camera and debt financing your new restaurant.