Fred Durst (Rock) stole Behind Blue eyes from the Who. Regardless of the genre, sampling will in fact - occur. If it happens, so be it. However, I do not see why this should discredit a genre as a whole? A lot of talent goes into hip-hop production, and flow/breath control/lyricism/writing goes into making a song/it's lyrics. It's not as easy as you think. It's truly not. Easier then playing/reciting a Led Zeppelin song? Of course, but it fails in comparison when comparing lyrics. The rhyme scheme is very basic. Meanwhile you've hiphop artists, leagues ahead of the game, using similies/punchlines/wordplay throughout their verses.
*This applies for underground hip-hop artists.
FYI - Groups like the roots, use live instruments in their music. Played by them. And they're hip-hop.
