...right. And Delegation of nameservice is a CUSTODIALSHIP for the end user organization/entity. The pain in .US was felt when some 3rd-level delegates took on a custodianship for free and then charged folks underneath them, a form of delegation-squatting, with no intent of sheparding the resource until clue was imparted to the more-appropriate organizations. That's just wrong, and triggered involvement of legal entities again.
Right on target, Joe. For the historical record, I would add that ISI eventually realized that .US subregistries were using the third-level domains as a cash cow. To deal with this, they imposed a requirement that the city/county government concur in new delegations for their communities. However, by that time the profiteers had swallowed up almost all the .US third level domains that had not been previously registered.