If this is proven to be true, surely that is an automatic sackable offence?
Telling a customer to shut up in retail or customer service would be instant dismissal. At a football match I would suggest things are different due to the raucous, high intensity atmosphere. When you say he was swearing, you don't mean at the fans i presume, but at the players? This is to be expected if so. You can't take your kids to a football match and not expect to hear swearing. If he was swearing at the fans this