If they have the money for it then it's their life. I can't help but feel a little envious of people that have such money that they can spend it on a bag (yes I know that they are said to hold their value and can be re-sold but still).
I received a Chanel bag as a gift once a long time ago. It didn't get much use from me because I am usually very casually dressed and it just didn't go with my other stuff. Anyway, after it having sat in my closet for maybe 10 years, I decided to sell it on Craigslist. Within a few minutes of putting my ad on CL, I had about half a dozen people interested in buying it. Mostly pretty serious and only one low-baller.
New, I believe the bag cost about $1,000.00 and I listed it for $800.00. I took the first person who offered $800.00 and sold it to them. I think it helped that it was a classic style - black, quilted leather with gold hardware IIRC and in excellent condition. I also had the box, registration card and clothe bag that it came in. The young woman who bought it really knew her stuff. I guess she'd been studying those hand bag sites.
Selling it was an interesting experience. I sold another one I had later on but it wasn't as much of a classic so it took a little longer to sell. I would say they do keep their value.