As someone who owns a FLGS (or, well, owns a company which is opening a FLGS soon, I should say) I've discovered Magic's secondary market is a necessary evil of being in the gaming business. People look at cards like Black Lotus and go nuts over the value they sell for, but what really makes Magic such an expensive game to play (and such a solid investment, really) are the $30-$50 things on the reserve list. A Black Lotus is only valuable to a collector, and it's not something a store will likely have in their singles case to sell, just because to get anything even approaching the value of the card, it can take years to sell it. Shocks and duals, the legacy playable planeswalkers, and the ten or so good cards in Standard, though? Those are generally in the $30-50 range, and you can basically be asleep at the wheel and they sell, because anyone serious about actually playing Magic is looking for four copies of those cards. I find it hard to give a damn about Black Lotus when there are cards out there I can actually turn around (and not have to have a separate insurance policy on) like the majority of legacy staples.
As someone in the game retail business, I *have* to be involved with Magic, like I said. Love it or hate it, it's just a part of the business. I've found there's infinitely more going on with Magic than pretty much anything else... and it kind of has my mind blown. The learning curve I've been on in the last month or so learning about the secondary market, investments in Legacy cards, speculation on value of new releases that haven't settled into a stable place in the market yet, etc... it's been nuts.
IN THE US? ASK ME HOW TO GET 10% OFF GAMES WORKSHOP PRODUCTS!