Latics chairman Dave Whelan has said the club will sack 29-year-old King.
Allardyce has now defended football players and suggested that King's was an isolated case.
Asked if he thought there was a problem with player behaviour in the UK, Allardyce 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."