I don't know that we have all the facts nailed down yet, but it certainly appears that 120v charging is less efficient than 240v charging. You may not care at your workplace, but you probably do care how much electricity you buy at home to feed your LEAF. If, as seems likely, you could reduce your home charging cost by something like 12%, wouldn't that be worth spending some money up front?
I originally thought I was going to get by with 120v charging only, but I changed my mind and paid Ingineer for an upgraded unit. I'm glad I did. Note that I kept my original unit, included in the car, and got a new upgraded unit from him; which will indeed cost you more than $700. But on the house side you only need an L6-20 outlet. Mine might as well be permanently wired to that.
So, why am I going through all this? Because now you can cut your "drag out/plug/unplug/put away" events in half. Yes, you are still doing it at work, but not at home. In fact, you might not even need to charge at work if you can charge twice as fast at home.
But back to your dream, it's only a dream, and I expect it will stay that way. What almost certainly will happen is that 120v charging cords will come down in price. The EVSE in that big black brick is likely to get cheaper, and smaller, and lighter. It might even end up being integrated with the wall plug. The J1772 connector won't get much smaller or lighter, but it too is likely to get cheaper. So, it might in time seem like your dream has come true, though engineers will tell you it hasn't, really.
End of April 2013: Traded my 2011 SL for a 2013 S with charge pkg.