Yep, I just checked Uproar and Mayhem in DC and they are both selling terribly. I guess lawn sales seem pretty good but there are thousands upon thousands of reserved seats available. For Uproar there are some sections with only like one pair of seats sold. I'm skipping both tours as well as I have no interest in sitting through a glut of bands that suck just to see someone good play for only 45 minutes to a little over an hour or something.
Surprisingly Black Sabbath is selling somewhat badly in DC too.
But it's a huge place and prices are probably too high and turning people off so that may explain some of it.