Macklemore's "Thrift Shop" is hip hop, I think it had a large radio play, he got 5 times platinum single "Can't Hold Us" too
Also PSY's "Gangnam Style" is hip hop, doesn't matter if it was shit xd it had a lot of radio play.
2 rap artists sold 300,000 & 400,000 albums in first week today (and another one 100,000) so how can you say nobody listens to hip hop online?
There's so many rap artists that get radio play, online too.