There's a level of economic coercion involved though as well - "going pro" is only possible by pushing for riskier and riskier stunts. If you want to get paid to ski, skateboard, etc you need to be doing increasingly extreme things to risk your own health and safety. The companies do lots of risk mitigation once you're filming a TV spot, but to get to that level you already had to be putting your body on the line for years.