I don't need a new bike. The past few bikes I've bought have been used, because I need a bike to get from A to B. I'm not racing, I'm not biking the trails in the untamed forests, and I'm not leaving something worth a lot of money in front of the Metro. So I've bought off Craigslist.
I miss Chain Reaction, the non-profit bike shop, where they sold used bikes at a price I liked. Don't know if they had a secondhand license. I do know that when they moved I didn't see the selection of used bikes that they used to have. The City Paper has a story about secondhand shops getting harassed by the local DC government. And this is why DC doesn't have the same sort of bike shops as they do over the border.
Not everything used has the same value and the law shows no difference between used/old/ vintage/ antique no name brand and coveted brand stuff. Contact your council person or just bug Ward 1 Councilman Jim Graham to do something about it.