I told someone "NO" on PotC behind me for *continuing to "flash" their phone camera and it wasn't about me.. I have noticed on many rides people express it's their first time. I've been on Pirates a hundred times, but for some it might be their only, or first time. Besides i think they didn't speak english and maybe didn't hear the recording at the start of the ride... that or they are just selfish and rude.
Another time some teenage girl had quite the potty mouth, I mean really really bad, my son is 14 and has heard it all before. There were no little kids within earshot. So as much as I boiled for a 1/2 hour, I bit my tongue. (bit it hard) Wow, though, DLR is sure not immune to the garbage from the outside world.