what does "signaling to a bowl game scrimmage from a cheap seat"mean?
To Ward, as to Earl Rose earlier, the District Attorney explained that he had no objection to the removal of the body. Holding the receiver with his right hand, the judge waved toward the puddled humanity at the door with his left hand, motioning them to go ahead. The value of the gesture is doubtful. It was like signaling to a bowl game scrimmage from a cheap seat. The scrap was already resolved. The last havering human obstacle faded away, and the coffin rolled into the corridor. The widow was walking directly behind it, her gloved right hand once more on the gleaming cover.

Question

Answer

This is an analogy from a football game. A cheap seat is a seat that us usually high up and well away from the players on the field. So any motion or signal from someone sitting in a cheap seat is useless, since the players on the field cannot see it. Because of the circumstances, the signal is meaningless, really. A signal in a football game is a motion made by the hand of either the quarterback or coach to the rest of the players. If the signal is coming from a cheap seat instead of the playing field it is worthless, since no one can see it.