By my calculations, that much power usage would have cost me $38 if I were to use my price per KWh at home.
The mileage in an ICE would have cost in the neighborhood of $112 - using my Camry's average of 30mpg and a $3.65/gal cost.
Now, you managed to get many electrons for free, reducing the $38 cost even further.
I can think of plenty of things I'd rather spend $80+ on when I take a trip as opposed to gasoline.