According to Courtney Love, Kurt Cobain was up for the role of the drug dealer (eventually played by Eric Stolz), and she would have been the girlfriend, Jody (played by Rosanna Arquette). Tarantino denies this.

What he does admit to, however, is that he wanted Gary Oldman as Lance, based off of his performance in True Romance. When the project shifted from TriStar to Miramax, then they wanted Tarantino to play the role. He decided to play Jimmy instead, so they moved on to Steve Buscemi. He couldn’t do it, so they decided on going against type, and cast Stolz.