Because the extreme sport industry(mostly skateboarder owned) seen blading as a threat to their board sales in the US. In Europe, Certain parts of Asia, and South America blading is still thriving like it was in the mid-90s. Everything went to shit once it was taken out of the US X games.
Its sad that you see skateboarder/snowboarding companies, when do you ever see company that sponsors both skiiers and bladers?