The Premier League managers' pleas come after King was given an 18-month custodial sentence after being convicted of groping a young woman in a nightclub and then breaking her nose.
The Wigan striker is set to be sacked by his club for his actions after chairman Dave Whelan described the 29-year-old's conduct as 'upsetting'.
The King fall-out has illustrated the high-profile nature of the game in England in that the spotlight is constantly on footballers to handle themselves in the right manner and act as a positive role model.
And Allardyce has leapt to the defence of football players in general and suggested that King's actions were an isolated case.
Isolated caseAsked if he thought there was a problem with player behaviour in the UK, the Blackburn boss said: "Players make a huge contribution in this country.
"I think if you ask (Professional Footballers' Association chief executive) Gordon Taylor about how much charity work they do, it would answer your question.
"I spoke to him (Taylor) the other day and told him he really should put that out in the public domain, particularly at a time like this.
"We've got one isolated case which is very disappointing indeed, but overall, Premier League footballers and most of the footballers throughout the Football League, across the 92 clubs, do a huge amount for their communities and this country.
"(What has happened) doesn't help and it's a delicate situation, but he (King) has got what justice has served him."
WengerArsenal manager Arsene Wenger believes King should be allowed to return to the game after serving his sentence.
"I believe that you have justice and it's not my justice, it is the justice that England has decided to apply to his case," Wenger said.
"When he has paid his sentence, of course you would consider signing someone like that.
"Otherwise you would never forgive anybody anything. When he has paid his sentence, some clubs if they want, they will take him."
Wenger, like Allardyce, stressed King's situation should be considered "an isolated incident".
He said: "He is an individual and if you do what he has done, the fact that he has played football has nothing to do with it."