I could write a book. Perhaps my favorite was at the only Trader's Expo I ever attended, ages ago.
There was this one vendor, Scott Andrews, "Master the Gap". He was addressing a large crowd and discussing his strategy. As he was making his presentation people would interrupt with questions, some more decent, and some outright stupid. Well...
One old lady (must have been in her seventies) was not having any of it. She felt that these interruptions were preventing her from learning the secret that Andrews was belaying to all of us. So she started yelling in a thick Jewish accent "Stop asking questions I want to listen!!". People ignored her. She finally really got angry, stood up and made a fuss.
Andrews then said "How about I do the presentation first, and then I'll take questions at the end? Fair?" People seemed to agree. So he continues.
Then sure enough a minute hardly passes and a question comes. And then another. And then another and another. And Andrews duly answers them anyway. The lady totally gave up in frustration.
This illustrated an important point. The vendors are there to sell. They are not giving away any big secrets that will teach you to make money. Yet this lady, who was there with her husband, thought he was giving the keys to the kingdom away. Those interrupting with questions likewise thought it was their one chance to glean some secret. It was quite a sight to behold.
I also remember one guy in his forties, very clean cut, who looked eagerly at Andrews and goes "Do you also offer a signal service?", with this serious look like this was going to get him rich.
You learn a lot when you attend these events...