You didn't mention the tire size, but try different brands in that size. If you are only looking at one brand, all dealers will have the same age cause they are all ordering from the same warehouse. Seems odd that any size is that seldom sold that the warehouse would have only 2+ year old tires. They try to manage inventory better than that!
Tires are made in batches by model & size, and some less-used sizes only get made once or twice a year. More popular sizes get produced regularly, simply to meet continued demand.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL