Would demand for Sapphire go up or down if suddenly every member of this forum had a copy?
Not buying things from ebay won't lower the price overall. The demand has to go down or the supply has to increase across the market for the price to fall. If ebay was the only place you could buy Sapphire, then yes.
*OFF TOPIC BUT A PERFECT PARALLEL* Like the folks that tell you not to buy gas in the US on May 15th. I'm sorry folks, but the gas that you wouldn't be buying on May 15th was actually paid for refined two months ago. Not buying gas one day doesn't lower demand. As an alternative, you're buying gas on the 16th.
It's alternative versus replacements. If you want to lower gas prices, take the bus for a week or don't drive your car on the 15th. You've found a replacement for fuel (or transportation) on May 15th.
Not buying gas on a specific day does nothing to fuel prices if you're still consuming fuel that day. Why don't people pay attention in econ 100!!!!
Man, Venezula is killing me at the pump!