"...considering our country's largest energy and carbon footprints come from the predominantly coal-burning grid....Can somebody explain to me how using electricity to fuel our over-abundant needs to drive absolutely EVERYWHERE in our culture is an environmentally sound idea? " 

 Yes I can, thanks for your question. 

It's will take a couple of decades to put a halt to  excess human GHG emissions.  It's a big job.

We have a electrical grid now that is mainly powered by fossil fuel and nuclear power.  That produces a lot of GHG.  The goal is to go to a 100% renewable powered grid over the next 20 years.

If plugin hybrids and eventually pure electric vehicles take over from internal combustion GHG spewing gas guzzlers, over that time period,  then GHG from transportation will be eliminated.

If I buy a plugin hybrid next week and charge it off the grid, yes it will be using fossil fuel, GHG spewing power plant generated kwhs.  But it will still emit less that a gas guzzler traveling the same number of miles.

Why?  Because even with the inefficiency of the present grid, gas engines driving cars are far less efficient.  Only 6% of the chemical energy in the gas actually moves the gas guzzler forward.  Battery electric gets 20% of the chemical energy in the coal burned to the wheels.  Less GHG per mile by far.

But, if I invest in solar panels, wind, or biogas power, then I can power my car renewably.  By selling excess power back into the grid, I can even charge my plugin car with renewable electricty when I'm away from home.

If government subsidized renewable energy and plugin hybrids and energy conservation at the same level it now subsidizes fossil fuel, nuclear, and fuel farmed energy (ethanol); then my solar panels would pay off in a few years.  After that my electric "gas" would be free.  Just as free as it is GHG free.

With a deal like this, a gold rush manufacturing and selling these devices would ensue.  WW 2 like war production in this war on GHG would revive our economy and bolster our failing currency, with lower energy costs canceling inflation and our oily trade deficit (that funds terrorist supporting oil rich nations)canceled.

It's all pretty simple really.  Your initial confusion was mainly based on static thinking.  A popular skeptical theory that assumes that either the energy economy must be switched over instantly from coal fired to solar fired.  Or we must abandon attempts to get an energy revolution started.

This is going to take 20 years of good jobs with benefits, a revived economy and tax base, and recycling of the old energy economy into a GHG free one.  

With lower energy prices and domestically, locally invested consumer energy dollars.  Your gas money will go to the farmer down the road with a biogas power plant or a neighbor with a solar panel (at the equivalent of 66 cents per gallon of gas), rather than the exxonmob or saudis or conagra (for ethanol).

As far as over abundant driving in single occupancy hummers or plugin hybrids, plugin bikes and bike lanes, electric mass transit (buses and trains) , car pooling and so forth would be a great addition to this decades long energy initiative.  And of course as the grid goes 100% renewable so would the electric mass transit.