The guy in back in that scene actually has his gun in his hand and just fiddles with the silencer while she's shooting everybody. They could have at least showed him trying to pull the gun out of his waistband. Attaching your silencer is less important than getting shot. And he seems to be taking aim at one of the other guys.
But I do agree that Charlize is smokin' hot in this movie.
while you were at the movies.