A Vehicular Riddle for the Ages

Saw a Hummer on the road this morning.  It was huge.

Whenever I see a Hummer, I  pull alongside it and give the driver the Face.  The Face is somewhere between scorn and revulsion.  I do it every time, unless the driver is big or scary, in which case I just wave.

I can't explain why I make faces at Hummer drivers.  I guess I just don't like the people who drive them.  I know that's an over-generalization, but so is this next sentence.  I don't like anyone.

Maybe it's because I think Hummers...