Two men are being handed life sentences on Monday for shooting a stranger dead after a row in a queue at McDonald's.
Horace Campbell, 28, and Liam Douglas-O'Callaghan, 18, were found guilty of murdering Devon Scarlett, 32.
Scarlett and Campbell got into an early morning spat involving others at the fast-food restaurant in Brixton, south London.
They were escorted outside by security guards but the row carried on and the two strangers agreed to meet in a nearby street for a shoot-out, said Bobbie Cheema, prosecuting.
Campbell called Douglas-O'Callaghan to bring his "thing" or gun, she told the Old Bailey.
Scarlett appeared to make a similar call but no actual call was made.
Cheema said: "Horace Campbell was determined to avenge the perceived lack of respect that Devon Scarlett showed him. Devon Scarlett acted with foolish bravado, behaving like a tough guy, but whatever he said and did, he was not armed."
Campbell, who had been drinking, followed Scarlett into Marcus Garvey Way and fired three shots, two of them hitting the victim.
Campbell said: "You are not so hot now", before walking away.
Scarlett, of Croydon, who was born Raymond Mitchell, died a few hours later in hospital.
Campbell, of Anerley, and Douglas-O'Callaghan, of Tulse Hill, both south London, denied murder.
The court heard that Scarlett had become involved in "someone else's argument" in McDonald's at around 6.30am on April 17, last year.
Outside, Scarlett was heard saying he had been shown disrespect, and Campbell said Scarlett was "going to be shot in the head".
When people tried to intervene, Campbell told them Scarlett had been "too disrespectful and was going to be shot in the head" and would be "filled up with lead".
A woman had heard them agreeing to meet in the nearby street, "effectively, for a shoot-out", jurors were told.
Scarlett was the father of four young children.
Detective Inspector Henry Lindsley said: "Unbelievably Devon Scarlett's murder was triggered by the most minor of incidents that Horace Campbell chose to involve himself in.
"His arrogance and obvious disregard for life is evident when, even after Mr Scarlett walked away from him, he continued spoiling for a fight."