It does sound sort of rediculous. First, what future earnings? He was playing it for three years, 48 hours a week... Secondly,there was a warning, he misused it.

It's sort of like suing the manufacturer of a boat. The say "If you can't swim, don't use the boat". The person does, the person falls out, and the person drowns, and then the boat manufacturer is sued for lost future potential to walk long distances on terra firma.