How can a artist be a sell out?

like eminem for a perfect exsample...people think hes a sell out cause he doesnt talk about killing kim or making fun of celebs and **** and know hes rappering with them...14 years in the game and you expect him to rap about the same ****...the man is all most 40...then i guess 2pac would have been a sell out cause 2pac would have done the same thing... if growing up is being a sell out then wtf...BUT RELAPSE ****** SUCKED LMFAO (except beatiful)