In most cases it is due to companies wanting to avoid paying extra royalties for having the JP voice cast on more copies of the game. Disk space isn't really an issue with the majority of console games these days. --- "I'd rather betray the world than let the world betray me." -Cao Cao
The voice acting is often contracted out to an outside studio and requires the localizer to obtain a separate license from the game itself. Localizers apparently usually consider the extra expense to be not worth it. --- "I dont buy Steam games because when I buy a new PC, I have every game I ever bought already ready to download." - GoreGamer
They'd have to include 2 versions of each cutscene.
Audio and video is stored separately.
And yeah it's because of licensing and money issues. Most studios just don't have the money to license the Japanese audio. --- You say that you're fine but I know that you ain't You're looking like Hell and you're no f***ing saint