While it’s true that you hit a point of diminishing returns, there’s a sharp divide between, say, a $200 bag and a $20 bag. Technically a plastic shopping bag will serve the same purpose as a purse, but it’s likely to break in less than a day. A $20 bag might last a few months of daily use if you’re careful, but it’s going to have cheap/non-durable materials, have cheap findings, and be poorly made. At $200, the odds are pretty high that it’s going to be well made, use solid materials that will last, and have fittings that aren’t going to corrode, fall off, or break in a few months.
I have a designer wallet that I’ve used every day for over 15 years, and while it looks beat up, it’s still fully intact. I averaged about one every 3-4 years before I got this one.
See also: Cap’n Vimes boots theory of socioeconomic unfairness.