You're just as creepy as the folks in that booth for walking around filming booths are a convention and calling it "coverage".
Doing interviews with people is already done by MD and RXMuscle though. Short clips of the action are not as common. Also, I want footage that I can use in my supplement reviews that actually belongs to me. It's helpful in reviews when I have some background images/videos to go along with it, so a part of the reason why I do it is to have a database where I don't need to get permission from each company to use a shot.