Some might want to call you out on that 700+ mpg statement. That number is accurate for a human/gas hybrid bicycle chassis powered by a weed whacker, when you're mostly pedaling and only using the motor sometimes (it still produces more harmful emissions then a modern Ford F350, because it's a filthy 2 stroke with no emissions Controls. Isn't that amazing?).
If it's a series hybrid, then it essentially is an electric car, with a generator to maintain battery charge. That has some advantages, like being available for longer trips.
But because a person rarely goes more then 100 miles in a single day anyway, the pure electric has advantages too. It doesn't have the weight, space and complications taken up by a whole other power system.
Some people like the idea of keeping the generator as an outboard system, like a trailer. If it's a powered trailer, with an automatic steering control system to keep it in line with the car, then the car and driver won't even know it's there. Then you can detach it and only use it for long trips.
Oh, okay. To address your point:
You're confused about the costs. Fueling a car with electricity, at average electric rates, costs you the equivelent of paying $1.20 per gallon of gas in the equivelent gas car. $0.80 per gallon at over night electric rates. It saves you money.
Or you can look at it like this, your 20 mpg gas guzzler, when converted to electric, all else being equal, will cost the equivilent of gettign 50 mpg at current gas prices, or 70 mpg if gas gets up to $4 per gallon again (do you think that could ever possibly happen again? I do).
From a cost stand point, electric has it all over gas.
No EV guy likes coal, and almost 100% of them are just as enthusiastic about green, renewable energy. Even though a purely coal powered EV is still less polluting then a gas car. And only half our power actually comes from coal.
But more importantly, the car doesn't care where the elctricity comes from. As far as the car cares, you could just easily charge it up from wind, hydro, solar or geo thermal power.
The point being, it's the production of electricity that pollutes, and that has to change. But the EV itself cannot be held responsible for the pollution, because with green energy availability, the car would certainly be an integral part of a green infrastructure.