>>11616271most of the market for older editions is normies who can't into libgen
once a new edition is released, the price of older editions plummets to pennies, and often (especially with the moneygrab freshman texts in their 12th edition) editions are basically identical except for trivial changes, so you can save a couple hundred bucks a semester buying very slightly outdated books
Other than that you're correct, there's really no reason to ever use an older edition except for maybe some extreme unique fringe case I've never heard of.