Of course BB players get rated.
I've seen the services take a Calhoun offer and move a kid from outside the top 100 to inside it. All the time.
And its far easier to rate BB players - they play against each other.
Emeka Okafor was outside the top 100 and a late, late priority of UCONN. In the spring, Calhoun saw him play for the first time and said in 5 minutes, he felt like crying that they might be too late.
It took Calhoun 5 minutes to see something the guys with hot dog stains missed.