The model of vehicle you drive and the appearance of the tires and wheels would lead one to believe that these are performance tires, rather than mundane rubber donuts for an automobile.
If you check the specific model of tire that you are using, you can determine what level of performance standards would be applied to the rubber.
"Sticky" tires will give great performance in acceleration and cornering and will also have very low wear durability. The damage to the tread is consistent with your description of rough roads especially if that is combined with softer rubber compounds.
From the Tire Rack web site:
UTQG numbers are assigned to indicate a tires overall level of
performance and tread hardness. These numbers beginning at 0 for race
products and traveling north of 800 for some of the longest lasting
all-season tires, are nothing more than a general guideline to assist
customers in making their correct tire purchase.
A more comprehensive discussion can be found within the above linked location or directly at this link.