First, bandwidth is very expensive. No housing money is used to pay for URHnet bandwidth costs. None, zip, zero. The network bandwidth comes from the university computing group on campus, CCSO, and they pay for it from other funding sources. The more computers you have, the more packets that are transmitted and thus more work is done by the network equipment.
Network equipment can only process a limited amount of packets per unit time.
So, a fast computer can clog up the network, because it can send and receive its packets more quickly, and can process the information sent faster. If one or two of the computers on the network hog all the bandwidth, the entire network slows. If we limit what individuals can send, then the network remains viable for everyone by keeping bandwidth open for everyone. The bandwidth that you enjoy is also for the entire University as a whole. That includes all residence halls, university teaching departments, university operation departments, and users.