i agree, but in some cases ( i think it was in shanghi six ) they probably used the instrumental from that kanye song because licensing it from dilated peoples or whoever made the beat was a hell of a lot cheaper than licensing the kanye song with him rapping.
i mainly enjoy instrumentals that were produced as instrumentals. building steam with a grain of salt by shadow is one of my favorites, along with some vrse murphy stuff, kid koala, ratatat, and some other stuff that i cant recall right now