My dad financed his new GC because he got it at 0% for 84 months (and I got him dealer cost on the vehicle). It's basically free money and he's paying it off using investment income, rather than dipping into his savings to buy it outright, which would remove that cash from his investment portfolio, reducing his investment cashflow.
This is the same method my friend that owns the dealership employs when they have a 0% thing going on. Why dip into his cash, which makes him money, because it's invested, when Chrysler will give him the money for free and he can pay on it using cashflow from the investments without penalty?