You gonna suit for that!??? Whatever happened to ******* ACCIDENT! Geez this litigious society is going down the drain. If he has permanent neurological damage I understand, but just because? gET oUTTA hERE.
Seriously? He only should sue if he has permanent brain damage? When you run a business like that you assume the risk, and when someone on your property gets hit by a cart like that, you should expect to dole out some compensation. They probably have insurance that covers that anyway.