The main reason people buy a VPS or use a dedicated server is for reliability. My internet speed is around 30 MB/s which should, in theory, be enough to host several dedicated servers.
My internet, however, is shared throughout the entire house. In total we have 2 Xboxes, a Wii, 4 computers, and 4 smartphones running off of the same connection. If one of these devices decides to install an update, somebody decides to stream a Movie, or install a game on Steam any server I would be running would get a massive increase in latency.
My computer is more than capable of handling 50+ players but I would have to leave it running 24/7, drastically increasing my energy usage and my electricity bills.