Ya, I wouldn't suggest a single pay lease. The above is correct, the money factor is so low that you're under 1% interest rate. Maybe pay your fees up front so you're not paying interest on that BS, but don't pay any capital down or anything, as close to zero out of pocket when you pickup the keys as possible. (Again, basic dealer doc fees and stuff I wouldn't pay interest on and instead pay upfront).
I was explained (here actually) that the reason is this. You have to have the total value of the car insured, but GMF or whoever the lender was is the one that gets paid by the insurance company. Say you literally drive off the lot and a semi slams into you and totals the car. From my understanding any down payment can stay with the lease company AND they'll collect whatever they can from the insurance agency. Now realistically in this case I'm sure they would work with you to collect insurance and allow you out of the lease or into that of another Volt, but say half way into the lease that happens, it might be a fight to get back what you prepaid and didn't get to use.
Pay monthly, that way your liability is minimized. Let the lender fight with the insurance company on the value of the car to be paid out. You did everything legally, minimized your exposure by putting as little down as possible, paid monthly on time, and was fully insured. If they came after you for anything, tell them to speak to your lawyer and hang up.