When I bought my current used car, in cash, the dealer offered it on financing for 0% or 0.9% or something very low — no impact on the selling price. It wouldn't have been a terrible decision to take the super low interest loan and put the purchase money into my investment portfolio instead (just another form of leverage). I paid cash anyway, because I went in intending to, but characterizing all financing as extremely desperate is misguided.
If you're buying a used car from a dealer, with financing, you must be truly desperate. A lot of people are desperate, though...