In theory, the NCAA exists to act as an organizing force for the thousands of college athletes that participate in dozens of sports all across the country. Without it providing logistics and a structure for competition, it is argued, you'd end up with chaos and no real way for universities to compete with each other.
Fine. I can accept that argument, at least as it pertains to non-revenue sports. But I think that it's also important for us to understand that the NCAA's other significant mission, enforcing incredibly petty bylaws to help justify its enforcement arm, is arguably the best and most important reason for its existence.