Because the guy knows that if he says a word about the reality that it was in fact the fat kid's fault, the media will have a field day calling him a siziest monster,  Tumblr and the like will flip out and probably harass him, plus the judge may be fat too and any 'fat shaming' will ruin his chances of compensation.  Also, a kid that fat? Do you think its folks have the responsibility or wherewithal to have jobs or do anything to generate some money? Dude could be awarded thousands but the family wouldn't be able to pay out given the amount of food that fat bastard son puts away. Better to go for the big company with all the money than risk having your name dragged through the mud by paranoid victimising fat journalists, being spat on in public/have a drink poured over you for 'blaming a chubby kid', and getting maybe £2,000 out of it, just to then pay that to your solicitor/barrister.  Who knows, fatty might die the next time he goes dive bombing. Fingers crossed.