There are many service Industries that implement noncompetes. For example - doctors.
Banning non competes Will add an additional cost to established practices to bring on a new fellow or recently licenced doctor.
Most new doctors are a loss for the new independent practice for the first 2 years. If noncompetes were abolished, the money losing doctor would simply open a new practice once he has a steady book of patients.
I predict lack of noncompetes would push many independent doctors to not hire as many new licenced doctors. Those doctors have to work somewhere, and that means hospitals.
The inevitable results seems to be higher Healthcare costs for all americans