For me, this is reason enough. Promoting illegal plates via a stay of temporary protection, and selling these plates that were originally for poor farmers to bring a pickup for work purposes. Instead, they are selling the plates to anyone including foreigners who own luxury cars.
In many cases, to cross the border into Mexico, a fee of $450 USD goes to the cartels who manage different border crossings. In the states of Guanajuato, SLP, Tamaulipas, Coahuila, and more it is becoming more common. They have found a way to avoid paying for legal importation, legal plates, and tags. To see gringos with Mercedes who buy into this is truly disgusting. Why would you do something illegal that you wouldn't even consider doing in your own country if it were possible?
"Organizations like the Union Campesina Deomcratica (UCD) issue invalid" plates", identifying their members before the authorities, but the only plates that are valid are those issued by federal entities and then accredit the legal stay in the country through a permanent import permit (pedimento) or an invoice issued by a vehicle agency "
"Organizaciones como la Union Campesina Deomcratica (UCD) expiden "placas" no validas, de identificacion de sus agremiados ante las autoridades, per las unicas placas que tienen valicez son las emitidas por las entidades federativeas y para ello tienen que acreditar la legal estancia en el pais a traves de un pedimento de importacion o una factura emitida por una agencia vehicular"