Not really any more, but it definitely used to be very profitable.The dealers get a cut of the financing - in some case it can be more profitable than the sale of the car.
This used to be the case when banks were providing the finance; you'll still see it a bit in the finance arranged through independent dealers. But with the brands it's either white labelled at very low margin, or the car brand has set up a bank itself. It's an enabler to sell cars, with rather than commission driven.