Also, it's not the first time I've heard complaints that a lot of the writing keeps talking about how you are the Chosen One, the sole hero, and other crap that basically expects you to ignore the fact that there are dozens of people running around in the exact same area doing the exact same thing you're doing. It's really silly.
It's why I hate MMOs in general, apart from games like Eve you're living in a country/ world where the overwhelming majority of the populace is an adventurer for a living. I genuinely wonder how such a nation would function in the real world - what would be the effect of thousands of gold coins from ancient times being brought back into circulation on the economy? Would the local ecosystem would collapse like Christmas Island as roving adventurers plunder the fruits of the land and hunt the local beasts into oblivion?
I'd play an MMO which actually dealt with problems like this as the game went on; dealing with hyperinflation and resource scarcity, and a deadly arms race as magical artifacts from the depth os hell flood onto the streets.
Since the currency of old is precious metals, its likely that the metal would be worth its current price and not the face value of the coin.
As gold was put into the system, its value would drop. The nation would either make gold rare again somehow or switch to a new, less common currency base.
But that's unlikely. The most likely scenario is the death rate of adventurers would be too high to impact the economy co siderably. This would lead to rules and guilds being formed to prevent people from going out adventuring without enough training. Adventuring without a license would carry a huge fine.
Then, when things quiet down, it'll be discovered that all the old tombs have been fully plundered and a venturing will become a worthless occupation aside from escort quests.