I have encountered quite a few d-bag cagers while riding. It's amazing the crap that they do. I especially love it when they are within inches of my rear wheel!
...and since I believe that most cagers, especially those in my area, are complete idiots it wouldn't surprise me if the d-bag in front of you thought that it was you revving up at him. Most people in cars can't tell the difference in simple things let alone the sound of a H-D versus the Ninjette, even though there is a huge difference!