These days it's pretty trivial to do the digital equivalent of "jamming with your band mates" when it comes to sampling but in the 90s you had to develop an ear for it because the process of capturing a sample through to cuing it in your tracker was longer and a lot more painful than what we take for granted now. And you often had to create all of your own samples, there weren't web sites you could download these things from like there are today. Even percussion needed to be sampled if you weren't lucky enough to own a drum machine.

One of the reasons I got into circuit bending in the latter end of my exploration in music was because I craved that instantaneousness with electronic music that I had when jamming with my guitar.

As for Kanye, I don't pretend to be an authority on his music but the few tracks of his I have heard haven't exactly been imaginative when it comes to sampling. He has taken tracks that were already good, taken the main riff from them and looped that. So I'd argue the creativity in his music is the lyrical content rather than his use of samples. Whereas you compare him to Daft Punk, Fatboy Slim or Prodigy and you can see that lyrical content is less important but the sampling is really creative, to the extent that the samples they've used are often unrecognisable from their original source.

edit: There's a YouTube video of Norman Cook (aka Fatboy Slim) talking about sampling using his Atari ST and how he'd hunt records for good sounding samples.

https://www.youtube.com/watch?v=qLjgXPDzeZo