I don't think the decision to raise prices due to the economic climate is just an excuse and there were probably a lot of long meetings because of the negative effect it could have.
Granted, increasing the prices would initially seem like a great counter to a declining exchange rate, however, increasing the prices will naturally slow down sales, initially at the least. A prime reason for the exchange falling is because of the economic climate and people have either less money or are spending less - therefore increasing prices could have an even greater negative effect on their profit because the consumer funds simply aren't there or aren't being spent at the present time.
Although the ultimate parent company may be in Japan, the sub-divisions incorporated in the UK can retain their profits until the pound is stronger and then transfer back to the ultimate parent company at a better rate so a declining exchange rate may in fact be used simply as an excuse...
However, given that Annual Financial Statements must be produced each year (although not sure about Japanese Business Law) and for larger corporations they will most likely have to produce quarterly statements for their shareholders, I don't think the UK incorporated divisions would have the luxury of holding onto profits for an extended duration as the parent company in Japan would obviously suffer when they have to produce their financial statements showing reduced profits because of FX rate deficiencies...
However, provisions could be made for this and accruals made, which I'm sure shareholders would be more than aware of the fact that Britain will no doubt become strong again and therefore as it's typically the shareholders who need convincing then all should be ok.
This is perhaps just a few basic elements in what is probably a rather complex financial equation but I'm guessing there's probably a pretty straightforward method to deciding whether or not it's our current climate which is the reason behind the price changes...
If the prices are increased in the UK but the prices for Japanese retailers (where there's no FX element) aren't increased then I'd assume that it's our current climate that is causing the rise in prices.
If the prices are increased in the UK and in Japan then it's a load of old cobblers as the price increase in the UK should accomodate any predicted loss in profit and therefore a price rise in Japan shouldn't be required. But then they may be expected less sales due to the price rise and therefore raising prices in Japan to counter this...ah, round and round we go...where we stop we never know! lol
The worst part as mentioned is the 2nd Hand prices will increase because people will start comparing their prices with current new prices - which will have increased grrrrr