Those incentives come with costs. In their case, it was better to know they didn't have to worry about making a loan payment every month for years when their overall financial future was a little iffy at the time - prudent when the main income earner's health was failing. It wound up being the correct decision, as my father died a couple years later.
My last vehicle I had cash to pay for it. Manufacturer offered a $2k incentive to finance through their own financing arm. I asked, and there was no early payoff penalty. So I financed the car, and sent a check a week later, paying it off completely well before the first payment was due.
