Oswald, I pity you. What I find immensely funny is your assertion that sampling is the only reason these old songs and lines are remembered. No, they are remembered because they were hot, cool, driving, funky and otherwise just bada$$ and are the most memorable parts of the songs.
I also laugh because there are tons of kids playing Guitar Hero and Rock Band and NONE of the songs on those are current. Why? Because its all noise that is incoherent, especially for those games. My step kids all know the Devil Went Down to Georgia, but neither I nor their mother ever played them. Its all because of Guitar Hero, and that is one reason Guitar Hero is popular. Because there are actual memorable, moving songs! I'm still waiting for the screamo, emo Guitar Hero or Rock Band pack. No, wait, that will never come....
Why was Kid Rocks Sweet Home Alabama soooooooo popular? Because he wroter, er, I mean borrowed, er, I mean stole, the best parts of two songs. "Sweet Home Alabama" and "Werewolves of London", both huge in their day, remain so not because of Kid Rock's song, but because they are still great songs. Mush the two of them together, and you get his hit.
Since most of us are still alive who grew up with all these great lines and songs your point that they are popular is off. If we were all dead, I might give you some points, but not right now.
And, the people who contributed and created that great music deserve to get their fair share and due. I'd be less vocal about it if the artists themselves actually gave credit to the originals, but sadly, in most cases, they do not...