It's a status thing for some.
I do have to say though, I have a couple of fairly expensive handbags, a small one and a cross body messenger type bag. My DD had a fit for the larger bag years ago, so I floated her a loan for half of it and the other half was part of her Christmas present. Her husband would have had a cow if she spent that much for a bag. I really liked both of the bags as well and got the smaller one for myself, then thought about it for a few days and got the larger one too. They are classic looking bags so have never gone out of style and, even though it's been 10+ years they still look nearly brand new. There is something to be said for quality materials and workmanship. I'll also say I haven't bought another handbag since.
As far as shoes, I've only had one pair of very expensive shoes. They were purchased back when I was in my mid 20s. They were black 5 inch stilettos. Have to say, they were quite comfortable, especially being stilettos, and they lasted longer than I was able to keep wearing them. They were a size 5 and my foot spread out as I got older enough that at 5.5 to 6 I just couldn't comfortably wear them.