Possibly time travellers or aliens

As a frequent gig attendant for many years there is one thing that I have noticed over the years, no matter how great the band is, no matter how much moshing or slamdancing there is going on, at least one person in the audience is stood very still, not moving, like a statue! Now being a self confessed people observer this has got me wondering over the years, one conclusion I have come to is that these people are time travellers or aliens. So lets start with the aliens, so they see big crowds of people all facing towards a raised platform, loud sound vibrations are being emitted from this platform, what is going on? So disguised as a human being the alien goes to the front of the alter to see what is going on, not knowing the local customs thinks it best to act like a statue until a full report can be made.
Time travellers, so when/if time travel is possible, think of all the great gigs we could all go to? Jimi Hendrix, Bob Marley, Beatles, Stones, Led Zeppelin you get the picture, anyway there could be a time law that will not let the time traveller interact or move in any way, so next time you are at a gig look out for these people and if you get any information please let me know.