The big wait!

Because I was born with the misfortune of not living in The US or Japan, we Swedes get games later. In this case I'm waiting for Heavy rain. How much longer am I supposed to wait? One whole day longer than you Americans. This gets me thinking: Why just one day? I could understand the situation with Final Fantasy 12 or 13 or whatever the number it is. You'll have to translate all the Japanese to English, hire voice actors and get an ESRB rating. But the only difference between the US and Europe is the rating system. So why just the one day for heavy rain? I can't see anything that can be change with that extra day. Of course I'm happy It's not a month and I'm not angry that it's an extra day, just confused.