Don't know how to address this, but if people want to spend their time at a show they paid good money to attend gazing thru their phones, what does one have to say to that? But it's safe to assume, as a consequence of this, many performers will adopt a lackadaisical attitude towards the audience and treat shows like a rehearsal. Which is understandable, since these guys have long risen from the level of playing at a bar or restaurant where people are too busy chatting and carrying on, and expect people to pay attention to the performance they are offering.
What they perhaps fail to grasp is that today's concert audiences care less about the music than being seen at the show or the subsequent bragging rights that go with having attended the show.
Welcome to 2018.
