Not sure if I am reading the OP correctly. If we are talking about bands not known for their looks, ie: Nothing special, and the marketing machine wasn't really trading on it, I would start off with Dire Straits, Steely Dan, & Supertramp.
If we are talking about, "Dang, these guys look _rough_," I can't go into the theatrical aspect (Slipknot), because they are in fact known for a certainly nasty look. Lemmy trades on his to some extent... The only ones that immediately come to mind are Lemmy's previous outfit, Hawkwind, and another British mainstay Tony McPhee (The Groundhogs).