As far as I can tell there are a vanishingly small number of problems where "new laws" are the optimal answer. Increased regulatory oversight generally leads to ossified markets with higher costs. Many of the most reviled monopolies throughout American history got there in no small measure because of government protection in the form of "regulation".
In this case, there are multiple car manufacturers available to Americans from around the world - if this makes GM vehicles more expensive or causes a consumer backlash that damages sales, GM will change their behaviour. That seems like a more responsive mechanism than piling on new regulation to dictate which types of fees are okay and which aren't.