I agree with you completely.
It was most definitely the stylish younger set buying pre-loved vintage Chanels in dress agencies (consignment) and even charity shops (goodwill) at a time most older ladies felt those 1980s and early '90s shoulder flap bags with heavy gold chain dated them (my mother included) that has fuelled the market ever since. If investment's someone's aim, you are entirely correct.
However, looking for defunct bag makers like Koret, Bellstone, Lucille of Paris on- line, names that are quality assured, buying at vintage fairs (where you can see/feel the quality before you buy) whatever the name, or as you point out, buying the many many wonderful bags now that are not quite so fashionable (a few Chanels included e.g Cambon) great deals and not refuelling the market can work. We can only try.
I believe for some makes there is actually more prestige carrying a vintage than new, the very first Bal Moto bags, vintage LV trucks, Gucci enamelled silver from the 1970s, very hard to recreate that kind of cache whatever and however hard the present day companies try.
