We are lucky in my building, there is a fenced-off "bullpen" full of new and used tires for our mechanics to select from in order to have comparable tread on both sides. I am fine with having used, mismatched rubber in the summer; come November, they will pull whatever I have off the car and replace it with new mud/snow tires which I need for my miuntain route.In the mechanic's defense, often new tires are not immediately available without calling out the service truck, which requires approval. Perhaps some are forthcoming.
I have maybe 30 tires of various shapes and sizes on hand, but new tires are usually 2 weeks away. I have to fax in a requisition form and then wait for the office to submit it to our supplier to fill it. Given the "middle man" is there, sometimes I get duplicate orders at the same time, last order repeated instead of the current one, or not at all. Sometimes it's a real crapshoot. We say "Ordering parts is like a box of chocolates....."