The use of sampled music

By chance I just heard the single Holy grail by Jay Z and I was completely dumbfounded by the sampling of Smells Like Teen Spirit by Nirvana to me it seamed jarring as hell. So my conclusion is that it only was used because Jay Z had to much money lying about, discuss.

Here is a video of said song if needed

So to be nitpicky, that's not sampling, that's interpolation. Sampling is when you straight up take the audio from another recording and use it in another recording.

I mean, I bet that's a pretty big part of it. But it also works with what the song is trying to say: Jay-Z is, at the end of the day, an entertainer. He might be a real person and all that, but do we actually give a shit? No. So here's Justin Timberlake singing Nirvana lyrics. You'll talk about that and you'll be entertained and I'll get my money.

You could argue that he just wants to turn heads, and at some point you're right. But the dude had to have chosen those lyrics for a reason. When you're at that level of fame as a rapper, there's no part of your image that isn't super carefully crafted. Maybe aside from Kanye, but even when he's just spouting shit nonstop he still wants people to know he's a radical.

Grammy Board recognizes sampling as a form of songwriting: http://www.wonderingsound.com/news/grammy-board-finally-recognizes-sampling-form-songwriting/