I also checked the ARIN database. Many of those cable companies
with 24/8 allocations appear to be @home franchises. The obvious
one is rogers@home. I sure do not see any RoadRunner space in there.
Also, there is NO allocation other than @home/s to about 24.100 so you are
right that it is not a /8 , it is closer to a /9 now. Does anyone else
have a buffer a fraction of that size? Those other 24/8s are sure
jammed in together.