Musicians are the biggest culprits here - they just play louder when the venue is open. And they claim they know what it sounds like in the house when they’re NOT in the house. If band members were less narcissistic there’d be 80% less drama to deal with all the way around.
Funny story about sound checks and this comment.
A few years ago I was a volunteer stagehand for a benefit concert. We had Stephen Stills as the headliner (yes, that Stephen Stills). It was just supposed to be him and an acoustic guitar (no backup band).
He brought his own inears and his own tech. He spent forever getting his in-ears, his guitar, his mic, the floor wedges (on top of the in-ears) just right.
For a guy who was only going to play 3 songs, it was one of the longest sound checks I'd ever experienced. But hey, I was put in charge of his wedges, so I was extremely honored just to be around this living legend. But woah, sound check went for hours.
Later that night, when it's his turn, he comes out and just absolutely blows away everyone with the first two songs. He lived up to his legendary status.
Right before the 3rd song, he sets down his acoustic guitar, walks over to the house band, asks to borrow that guy's electric guitar, takes the guitar he's never played, pluged into an am he's never used, walks up to a different mic, and plays the 3rd song, rather oblivious to the fact he is no longer in front of the wedges he spent so much time getting just right, with lord knows what running into his inears since that mic was never routed to them. He still killed it, and it didn't impact his performance at all. The audience goes wild. And I'm just like, wtf did we spend hours on a sound check when you didn't even use the same mic, wedges, or even the same guitar for 1/3 of the performance?
Don't get me wrong, I'm still honored to have been a part of it, but it just cemented in my head that sound checks are mostly pointless.
On a different note, Kenny Arnoff has said when he tours with Joe Satriani, there are no sound checks. Joe Satriani apparently doesn't belive in them either.