I Was Only Trying To Make Conversation

I was third in line, behind a woman and a man at the soda fountain in the cafeteria today. The guy in front of me observed the woman pressing the little square button that dispensed only unflavored carbonated water into her cup, and the following discussion ensued:

Man: Oh, I see you like the bubbly water there!

Woman (somewhat embarrassed): Oh, uh yeah I just kind of like the carbonation, I guess. I don't know why...

Man: You know, in Italy when you ask for water in a restaurant, they give you sparkling water by default unless you explicitly ask for tap water.

Me: Well, that's because their tap water gives you explosive diarrhea.

They both kind of shot me big-eyed stares and wandered off in opposite directions.

And people wonder why I rarely speak up at parties. *shrug*