^Speaking about TBs only since I don't have any Pandora, it's not about the cost of the material. It's about the ability to put your own bracelet together, reassemble at will and the enjoyment of wearing, collecting and sharing the beads. It's not something you can be persuaded into; either you get it or you don't. Also, TB has been around since 1976, so if it's a con, it's been working for a long time!
I have Tiffany & Cartier pieces and they are nice. But anyone with the $$ can go into the store and buy the exact same thing. Where's the uniqueness, the "it" quality that makes it mine? With beads, anyone can buy the same beads, but the chance of someone assembling their bracelet exactly like mine are slim to none.
It's like the Louboutin shoes...people love and pay huge amounts of $$ for them. I don't get it; once you put them on and the red gets scratched, doesn't the value immediately plummet? I'd rather get a few (or lots!) pairs of cute shoes that I don't have to baby as I clomp about town or sit prettily on a stool. I obviously, don't get it.