2018 MAZDA CX-3 Wheels Problems

I WAS SOLD A VEHICLE WITH "NEW" TIRES. I'VE ONLY HAD THE VEHICLE ABOUT 6 MONTHS AND FOUND OUT THE TIRES WERE MADE IN 2011 AND STARTING TO DETERIORATE SO I HAD TO BUY ACTUAL NEW TIRES. I DID NOT HAVE AN ACCIDENT BUT FEEL THERE COULD HAVE BEEN A TIRE BLOWOUT. LUCKILY I HAD RUN OVER A BOLT AND WAS TRYING TO GET A TIRE REPAIR WHEN THE TIRE PLACE TOLD ME ABOUT THE BAD CONDITION OF ALL FOUR TIRES. THE DEALERSHIP FIRST DID NOT BELIEVE ME BUT WHEN I SHOWED THEM A PICTURE THEY SAID THEY CAN SELL TIRES UP TO 8 YEARS OLD AS NEW IF THEY WERE NOT PREVIOUSLY ON A VEHICLE. I DON'T KNOW IF THAT IS TRUE BUT IF THE TIRES WERE STARTING TO DRY ROT IT SEEMS LIKE A BAD IDEA AND CERTAINLY UNETHICAL IF NOT ILLEGAL.