A few reasons:

1. Everybody knows J. If you were involved in hardcore or underground metal in the 80s, you knew J. It didn’t hurt that J sweats coolness.

2. Likewise, everybody knows Lou. And most people LOVE Lou. Hell, I hung out with Lou when I was 16 and it was incredible (http://nmh.livejournal.com/3336.html).

3. J’s guitar playing broke punk. While he was a super competent guitarist in era of less than competent guitarists, he still used the shitty Jazzmasters everybody else was using. He was an inspiration from a technical perspective.