[nosuchthing]

There's a wide variety of people and motives at play, and there's not cynicism in taking note of folks who are out to collect instagramable moments.

Just as many people find it more enjoyable to play with their phone instead of paying attention to their local environment, there are people who find it more enjoyable to broadcast "Look at me, I was here", rather than participate locally (many often do both, but there's a noticeable amount of folks who don't participate and only document, be it photographers, or selfie obsessives). Taggers share the same mentality. Also concerts and events in my city are often free, so it attracts a more casual audience who's bored enough to have left their house and yet not invested enough in the event to be engaged or participating.