Would I be the asshole if I report that a neighbour makes the sidewalk dirty?

There is a neighbour building that has car access into the property, but to make space for more cars, these are not parked in asphalt/concrete only like usual, instead some cars are now regularly parked on (what used to be) their garden.

Even though I think it looks horrible that cars are parked on a previous green area and their previous green surfaces have become a mud monstrosity, that is none of my business. What bothers me on the other hand is that when the cars leave the property from the mud that used to be the garden this is making the sidewalk full of mud as well, dragged by the car wheels.

Would I be the asshole to report in Sag's Wien that this behaviour is constantly making the sidewalk dirty from mud as soon as there is wet weather? or am I overreacting and being an evil neighbour?