The usual phrase in warranties is "defect of materials and/or workmanship". So any issues that come from exposure or wear are not covered. Poorly engineered parts can be a gray area. The company can say the product worked well on delivery and only because of how it was used did the problem come about. They could also say that a loose or wobbly freehub body does not create a safety problem of prevent the wheel from working. And if I have read post #3 the OP is still riding that "defective" wheel
Warranties are far more about liability limitations and public relations then how stuff really works. Andy