Most major companies don't see racing as a wise investment; they would rather put their money in the major, so called, "extreme sports." If you look any type of riding, from BMX to motocross, all of the major sponsors are on the dirt jumping/freestyle side of the sport.
This holds true for mountain biking, while racing is going by the waste side, freeride events are growing in popularity (which isn't a bad thing). Most of the riders who are coming up in the sport of mountain biking, aren't really known for their racing skills, but for their jumping/hucking skills (Again, not a bad thing). The only problem is, it's killing the racing side of the sport.
All in all, it is pretty sad that NORBA doesn't even have enough money to pay the winning riders in the pro-class. I was truly amazed to see as many top pros in Big Bear, CA. as I did.