Look at Dean Wilson's issues this year. Had a 450....didn't have a 450. Still eligible for lites, so he does that to keep current and viable for sponsors. If he hadn't been eligible, then what? Buy a stocker and try to make the main?
Not quite as bad as in motogp, but it does boil down to few competitive rides available.
I guess your get up and go needs a coffee. - Drif5