I heard a loud clicking noise while driving to work one day and pulled over to check. Had an "eggbeater-type" mixer sticking out of my tire sidewall. Shop aske

I heard a loud clicking noise while driving to work one day and pulled over to check. Had an "eggbeater-type" mixer sticking out of my tire sidewall. Shop asked if they could have it for their countertop display of weird stuff they pulled out of tires. Anyway, they recommended replacing both front tires, but I only did the one and it was fine. I understand the reasoning, I just don't agree with it because tires simply don't wear at the same rate.