Not entirely true, I don't think they bother. I'm approached by folks offering "need a taxi" on a regular basis. This is common at most every and any airport I've ever been at, including IAD.

As far as lines go - yes, they definitely exist unfortunately I get to experience them on a regular basis. The last one was thursday after that snow storm about two weeks ago (weather was definitely part of the issue) - it was an hour wait and they were doubling & tripling folks up for the ride.