One cannot operate a ski school or any business enterprise on US Forest Service land without appropriate permits. That is what differentiates US ski resorts from the European schools. The resort obtains the permits. This also serves as a revenue stream to the Federal government via the fees.
Go try and open a business without the requisit permits on federal land and see how long it remains in operation.
If Mr Harb is an employee of the local ski school and revenues are paid to that entity and the permit holder pays Mr. Harb no law is broken. If the money goes directly to Harb it is another matter.
One other consideration involves insurance and liability.
There have been instructors attempting to circumvent the system and teach out of the parking lot for years. It eventually comes to an end.
I'll tell you who usually stops it and that is a local instructor who alerts a Forest Service investigator.