A live musical performance can be a very powerful experience. It is ephemeral compared to the plastic arts such as painting, a painting, once it is made, does not vanish after an hour like a good concert. A painting lingers on in the physical world for years and years.
My thought is that when someone is on stage performing that there is a sort of nourishment that is happening that is akin to a baby at it's mother's breast. The feeding in this case is spiritual in nature. And though the performance is a here today gone tomorrow sort of thing, the experience can and often does leave the audience with a sort of food for the soul, that becomes a part of them, even, in a sense, forming who they are and who they are becoming.
This was never more apparent to me than when I saw the band U2 in a comparatively small venue in the early 80s. I left that old church, after the show, with a deposit of something very powerful -- I would have been hard pressed to define it, yet I knew somehow, I had been changed forever.