Don't be that guy. We have this one visitor who comes by at least once a year who is really disruptive. He is a nice guy and well liked so we tolerate him, but the worst part about it is that he doesn't even know that he is being disruptive. In reality his mere presence is disruptive, he doesn't have to say or do anything, he just has to show up and chaos ensues. The worst part is that he thinks that everyone is just literally falling over themselves to help him. I heard a an interesting Japanese sentence that immediately made me think of this visitor. あの人と出かけるときは必ず雨が降るので(Ano hito dekakerutoki wa kanarazu ame ga furunode) which means "every time you go out with him it rains." Decorum is the better part of mastery. The moment you become a student of the martial arts you are expect to act like one. This goes for black belts and teachers as well. What one does off the mat is often times more important than how one performs on the mat.
This person who visits our dojo forgets that he is required to follow the rules and etiquette of the dojo but instead he chooses to act like nuisance. In Japanese they say あたまかくしてしりかくさず (atama kakushite siri kakusazu) which means that someone who "hides their head but forgets to cover their butt."
When you visit other martial arts schools, please act accordingly. It reflects poorly on your teacher, your school and ultimately you.