Anyone can research the laws for any area in North America but I just looked up the legal definitions that apply to commercial vehicles in Alberta. I expect that similar definitions apply in most jurisdictions. Note that there is no mention of charging a fare in the definition of commercial, just that the vehicle is used to provide transportation and does not meet the requirements of a private passenger vehicle.
“commercial vehicle” means a vehicle operated on a highway by or on behalf of a person for the purpose of providing transportation but does not include a private passenger vehicle;
“private passenger vehicle” means a vehicle used solely for personal transportation,
not including, in respect of a person’s business, work or employment, the carriage of passengers or of goods, except for sample cases or display goods that are conveyed by a salesperson and that are not for delivery or resale;