They only mention that the company pays for the internet service but I'd assume traffic/speed from a home could also be an issue. I mean the average home network connections aren't exactly amazing so what can be hosted on these servers (I doubt it's cost efficient to provide new infrastructure for every home)?
Isn't residential DSL and cable a shared pipe, thus if they are using saturating that 50mbit pipe 24/7/365 then your own DSL/cable connection could be considerably worse?