Nope, they rent from Amazon's S3 cloud.
They create such a server load that Amazon yells at them whenever they do something profound enough to spike the traffic.
What exactly would they do that would cause a spike in traffic?
Edit: Hey Bone, when we swap server hosts, is there any chance of us having a new pre-1.9 map so we can test rp, just for the sake of it? I'm not speaking for everyone, but I personally am a bit bored of this map.