Why are some promoters against DSLR's going into gigs? I had a ton of trouble last night from security/door staff even though my presence had been requested by a band and I was on the list. Apparently if the promoter doesn't know I have a camera (boo hoo?) then it's a no go.

What is this madness?????!? Previously I've had my bag confiscated, been manhandled and generally never given an explanation why DSLR/SLR cameras are not allowed into gigs.

Any ideas? I get the impression it's something to do with money, the press and rights. But no one's given me an answer yet. If a promoter on here knows it would be great to know why they do it.