It must be popular in certain regions. I hear in Toronto thousands of people showed up last year, but here, nobody's heard of it.. (even though there is a march organized here.. no ads anywhere, its weird)
I already know I can't make it either, I won't even be in town. Although it would be irritating to me to show up at a marijuana legalization event in a town with probably 400,000 pot smokers and have only a handful of people show up. On the bright side, these events seem to get better organized every year. When everyone starts showing up, the laws will have to change.