Throwing things on stage is bad concert etiquette - but it's also not a new trend 

The recent spate of incidents where objects have been thrown at musicians by people who paid to see them perform has generated comment, consternation and condemnation on media both mainstream and social.One recent case involved liquid being thrown on stage during a performance by American rapper Cardi B. The singer retaliated by throwing her microphone into the crowd. Media accounts suggest the incident has resulted in a police complaint filed by someone in the audience.
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