If like many Washingtonians you never leave NW, sure. But there are plenty of billboards in NE and SE. There are definitely billboards when you get a little ways out on 66, also on 50E towards Annapolis. 95 in VA is non-stop billboards, I forget if 395 has them. The one I'm not certain about is the beltway ... but pretty sure I've seen billboards on the beltway in parts of MD. There are (were?) also what amount to billboards along H St in NW. So I have to disagree, and encourage you to explore the area more.