Agreed.
I think it would be more effective deterrent if VIZIO had to work with those third parties to locate and delete the material that was transferred to them. This 1) would nullify the contract between VIZIO and those parties forcing VIZIO into back payment and 2) create an annoyance for the third-parties, hopefully making them think to ask how any data they're purchasing is being collected.
At a minimum I think that customers whose data was collected prior to March 2016 have a right to know which third-party companies purchased their information.