Well the immediate technical reason is that they don't have a FIM roadracing license. They don't have a FIM roadracing license because they haven't first gotten a national professional roadracing license and then applied and qualified for the FIM roadracing license (not easy). They haven't gotten a national professional roadracing license because they haven't gotten an amateur roadracing license and then qualified to become a professional (not easy). And, while just about anyone can get an amateur roadracing license, I suspect those particular doofuses haven't gotten one because relative to world-championship-level riders who have proven their worth, and their safety ... they suck. And they don't want to prove that they suck by actually getting compared to other riders who don't suck.
Disclaimer: I'm 20 seconds a lap off Jonathan Rae's lap times at the small number of tracks where I have been able to make a comparison. I got about halfway along the steps listed above, about 20 years ago, and I ain't gettin' any younger, so it's a fair bet that I won't be gettin' any further.