The internet was not built by the users (as they are known today). It was designed and built by the department of defense, for the military to use initially. They let some universities make use of it since several helped research, document and build it. They (The DoD) enjoyed the benefits of letting academics contribute to the technology. It grew organically over time into the complex set of networks and implementations you see before you.

Interstate highways were created in the same manor. That is fun reading if you research it a bit.