When was the last time anyone was frisked at the door? In the 80's you used to get the cursory pat down, but nothing now. I think these days, everyone is too shit scared of being sued for touching someone inappropriately to worry whether they are smuggling anything iffy into the gig.
Re cameras, I often take a compact digital to gigs, for pics before/after with my mates or to get pics when the band are talking or during ballads and my interest is waning. As far as I know, all you might be stopped for is a huge great lens on a camera, like some the sort a pro photogropher might have. They can hardly stop you taking in a small camera when everyone is taking one in anyway courtesy of their mobile.
You couldn't buy me with a million babe