International trade is priced in USD regardless of local currency, hence when the Yen gets strong, you hear Nintendo issue a press release bitching about reduced profits from outside Japan because they are getting less Yen for every dollar since their accounting has to be in Yen.
The USD has been tanking for a couple of years now which means for places like in New Zealand where the exchange rate used to be 2:1 to the USD is now nearing parity, which means by keeping the local prices as is, effectively raises the prices against us. (An Australian dollar now buys $1.11USD)
At present the 3DS sell in America for $250 retail, which means it should translate to $285.95NZD. However this is not true, It actually retails for $480NZD or
$419.65USD.
A premium of 68%! Now we do have sales tax of 15% that is pre-calculated into the price which mean $55USD tax, but that still leaves us at $365USD over a hundred dollars or 46% premium.
At the new price, $170USD, it should work out to about $200NZD. Keep in mind this is just for the console, the same price inflation extends to the games which are price between 80 to 90NZD or $78.69USD on the top end,
almost double North America. This example is just New Zealand, but it is a pattern repeated in other western countries where the prices are pegged arbitrary are according to publisher. This even extends to online game purchases like Steam which can be quickly checked
here. For example, there was a Steam sale of Civ 5 for $17USD, but here that same sale was priced at $27USD, $10 dollars more for exactly the same thing.
Hence why the USD is important.