That Watford 'goal': should we have 'played fair'?

There has been some suggestion that we should have allowed Watford to score after the travesty of the first Reading goal, to even things up and allow the game to carry on in a spirit of fair play. John Ashdown at The Guardian thinks so, and he opines that by not doing this we have somehow contributed to the pervasive atmosphere within football of poor sportsmanship and a disregard for fair play:

Why should football abandon all ideas of fair play and sportsmanship?