I hadn't seen this posted yet, so I thought I'd mention it. I saw some posts on this originally just an hour or two after it happened, from friends of mine in Nashville that were also close friends of the deceased.
Details are still a bit vague.. but it seems that this musician was smoking in a non-smoking area (well after the bar was closed), and this somehow escalated to an incident where the club owner shot the musician in the back of the head "out of self defense".
Bar Rescue, for it's part, pulled the episode that was set to air where they were to rescue this guy's bar.. but they forgot to pull the replay.. so the episode aired around midnight or 1 AM EST. I watched it.. it painted the guy as a stereotypical shady version of a club owner.. but the guy had a terrible temper, and even his own mother said he'd become "mean". Creepy, knowing what we know now..
RIP to Wayne Mills... and man, it's something to make you stop and think, because I know I've had times where I've been in a heated arguement with a club owner over things way more important than a cigarette.