But, rock stars are not going to arrive early every night just to stay alive. The buck has to stop somewhere, and EVH decided it was in the bowl of M&M's.
For one, the same people in charge of safety like riggings and electrical are not going to be the same people that are supplying the refreshments.
I can also imagine a high number of people like myself reading that part and think it's a joke or purposely ignoring it because there are much more important issues to deal with and because I'm not much into indulging the ridiculous whims of self important people.
It doesn't say "no brown M&Ms;" - it says "no brown M&Ms, otherwise we cancel the show and you still pay us the entire amount".
If I saw something like that in a contract, maybe I wouldn't go looking for brown M&Ms, I'd at least ask my boss (who hopefully has a direct line to our lawyers) "is this for real?", and if my boss and our lawyers are any good they'd tell me that's as real as it gets.
Then you probably wouldn't be working at a concert venue / on a showbusiness production team anyway.
Edit: have you seen a Van Halen (or, really, any stadium-headlining) show? The entire performance is "the ridiculous whims of self important people". That's kind of why we like it.