A selection of the numerous responses we received follow:
Robert W. Kingery: A tie: cell phones and TALKING!
Bobbi DiFalco Parsons: Someone texting during the show. The bright light is so annoying!
Carli Entin: Cell phones are the worst. I want a t-shirt that says, "Your texting is interfering with my abiliyt to suspend disbelief."
Flirty Flipper: Cell phone lights. People checking texts.
Kelley Cheetham: Anything phone related. I once had someone sitting in front of me who ANSWERED his phone in the theatre during the show.
Dantvman: Live tweeting live theatre. Just having your phone out in general during a show. Please be engaged.
daspion: Pulling out the phone for any reason during a show. It's like a beacon in a dark theatre.
miss_farin: Texting during the show. Put your phone away!
jenn4037: Using cell phones to check the time!
Sue Manger: People who must check their Facebook during a show.
Danni Horwitz: When someone actually answers the phone during a show.
Singing or Talking:
Lisa Pack Finnicum: I really don't understand why people talk through the overture of a show. You know, the overture sets the mood and lets the theatre goer begin to slip away from the world and into the fantasy of live theatre.
David Landrum: Talking during the overture. It is part of the show, too. The orchestra rehearses it and should be enjoyed without people in the crowd talking until the curtain rises. Once the announcement begins, talking should cease.
Tara Ryan Faupel: Talking and singing along with the songs.
Juan Luis: People singing along at a musical!
David L. McCurdy-Waterhouse: Talking people and those that decide they want to sing along with the performer.
Amy Boyles Martinez: People who sing and hum along!
Tracey Tinder: I dislike GREATLY when people feel the need to sing along with the cast.
cenoite: Talking during the show, or singing along.
lauren9739: REPEATERS! I heard the joke the actor said, I don't need you to repeat it so I think miss all the new dialogue.
Ronica Marsh: Late people sitting in the middle of the row.
Jeanie Wrightsman Diamond: When people come in after the show has started!
Robin Richard: In general: Latercomers who arrive 10 minutes after the curtain goes up.
Debora Seltzer Cosell: Latecomers. Plan to arrive early so in case you hit any obstacles on your way to the theatre, you still wont interrupt the experience of everyone else.
Simeon Katherine Herring: People that come late! Is it that hard to be on time?
Nikke Nason: Coming in late!
Hilary Brugger: People who rush out to get to the parking lot first during curtain call.
Garrett Canna: People who leave during curtain call.
Nathan Hinds: People who leave during the curtain call.
Liam Gibbs: When people get up and leave during curtain call! No respect!
Taking Photos or Video:
Andrew Hollis: People who take pictures with the flash still on.
Will Lewis: People taking photos and or videos when explicitly instructed to not do so. I am a stage manager and it is infuriating when audience members do this. Even when they think we or the ushers can't see them. WE CAN!
Sparkling Diamond: Flash photography.
Marc Miller: I hate when people take pictures, or even video tape some or all of the production.
Marck Hernandez: Those taking videos and pictures.
Crinkly Candy Wrappers and Eating During the Performance:
Jeffery Wines: OMG!! Candy wrappers!
Ron Hallsten: The person sitting next to me who brought in a pastrami sandwich from a deli.
Valerie Roberts: The sound of cellophane crinkling in someone's hands as they open their bags of candy is like fingernails on a chalkboard to me!
Richard Buman: Candy wrappers. Specifically, the people who seem to think if they open the wrapper v-e-r-y-s-l-o-w-l-y, it will somehow go completely unnoticed.