I was recently in Santa Marta Colombia where they also have that in effect. If you are caught on the road on an off day you not only pay a stiff fine but they also impound your car so you have to pay tow and impound as well. Not many people test it resulting in more passable roads.
Have you ever driven past one of the impound lots here in SD? The one on Colombia at the old dog track has hundreds of vehicles. Every few years they bulldoze them into a big pile of scrap.
Have you seen how many cars are impounded for lack of Marbete?
Stiff fine (for them) but yet they still take the chance.