Tire wear >>>> Alignment

If a tire is toed and 'scrubbing' you can get oscillations that lead to 'cupping' on opposite sides of the tire. Dynamically the whole tire just wiggling back and forth, causing uneven wear on both sides. People tend to think very one dimensionally and in terms of what their eyes see- "oh, the inner edge is camber"... or 'the tire wear seems uniform, just only got 8k miles on the set so the alignment must be good"