Interesting point. I personally don't consider my bags to be investments or worth "anything" in monetary terms in any event - from a technical standpoint they are insured but I buy bags that I consider classics and more importantly that I love enough to keep forever - I've never sold one. This means once the money is gone from my pocket it doesn't really make a difference to me how the market price moves.
I can see how opinion would differ, however, if selling on to recover at least a proportion of the price is built into your bag-owning model. And I do agree that it's up to the consumer whether they are prepared to pay the asking price.