Trucks often have to carry many different things, the most important of which is to run into construction sites to transport construction materials. On the way back to the city, the rubber bands will help the tires reduce the amount of dirt and sand that sticks to the wheels. If any driver lets dirt and sand fall onto the road, they will be punished by the authorities.
So the rubber bands tied to the truck tires are simply an effective way to clean the wheels before entering the city. And that is also the most accurate answer to the doubts of netizens in recent times.