There's very little culture of having table wine here in the US, and that allows pricing in the market to come a bit unhinged. And wine's heavy, and for most Americans it needs to be shipped in from far away. Even when it's domestic - I imagine the shipping cost to get a bottle of French wine to me is actually lower than the cost for a bottle of Californian.

Also, Carlo Rossi. I think a lot of us still haven't quite managed to banish the memory of that wine.