OK so these are called RMAs (Rubber Modified Aggregates). Cement or asphalt for the purposes of discussion are the same here.
When blended they are a cost saving of 45% over the life of the deployed product. That comes at various levels to add to that final amount but it goes something like this. Cheaper by the mile to make, cheaper by the mile to install as it requires less thickness of roadway to accomplish the same. Easier on the environment to install.
Once Installed.
Quieter roadways. Stays blacker longer , so therefore repainting of the road control measures are reduced. It doesn't pothole as easy. It stands up well to heat and cold and water.
A two-inch thick overlay will use about 2,000 tires per lane mile at 18% RMA ratio. This means that for a one-mile section of a four-lane highway, 8,000 tires can be used in creating a safer, quieter, longer-lasting road!
You can get out your calculators to see the market here.
PLUS those tires are further cost saving by not needing to go to landfill or etc.