Re: Acceptable reasons for you to get up from the drums mid song?
I've never gotten up during a gig, nor has any band member ever done so. However, a few years back in one of my old bands, we were auditioning a new bassist. Prior to coming out he decided that he wasn't happy playing the bass lines written so he came in and started playing his own bass lines he'd written for the music. This completely messed with the flow of the song and none of us were happy.
The guitarist and I got over it pretty quick and we finally got the guy to do the proper parts but our singer couldn't get over the guys arrogance. Within 3 songs and much heated conversation between our singer and the bassist, he was packing up and was gone without another word. He just stopped playing right in the middle of a song and started packing his stuff away. Was quite funny.