He looks up from his playing. He knew eventually someone would come while he was playing. It is impossible to be anywhere on the train alone except perhaps the quiet cars. But he didn't want to isolate into the quiet car to play. He is actually quite content to play where people will hear him. Because some people might benefit from the sounds of life music.

"It is meant to help calm ones soul."

The spiritual energy infused within the music is a healing component. Unseen all around them in the waves of the music as it fills the room.