I'm all for compromise
I go to a lot of gigs, mainly metal / rock and I pay a lot for the privillege of seeing my favourite bands perform. I like to take some photos to help me remember the gig, especially in years to come. In a way good photos that capture the atmosphere and performance posted on social media can be a great form of free publicity for the bands. However, I am mindful of those around me and when I do take photos, I try to be as quick and unobtusive as possible.
If someone who has paid a lot see see the show wants to experience it through a 4-inch screen, well that's their choice. However, they should stand at the back out of everyones way.
Some bands have the right idea as well - it's now becoming more common to be able to download the audio of the gig (sometimes free, sometimes for a small fee) soon after - Metallica and Red Hot Chili Peppers do this.