Yup. The first one I remember is a concert where I went to see the opener and didn't much care for the main act. While I was on the floor during the opening act, I was next to a girl who seemed similarly enthused about that band. We definitely both noticed each other fangirling over this relatively unknown opening act. Then, afterward, I bumped into her on the balcony while the main act was playing, and she's like "these guys kinda suck right? I think I'm gonna head out and get a drink at $nearby_bar". And I totally missed the hint.