How Expensive DVDs in Japan Are!

I offen talked with my Japanese friend about how about learning English with DVDs. I think it sounds good, but I guess I cannot understand almost contents of DVDs in English.

So I tried to find a kind of DVDs which I don't gave up to watch. I think the followings are best:

• Knight Rider
• Airwolf

Both are American tv shows which I watched in Japan eagerly when I was a child, and I will be able to remain the stories of the DVDs when I watched them.

I checked prices of the DVDs and I was very surprised at the difference of prices between US and Japan. Here are some examples:


Knight Rider - Season One: $16.49(US, 1185 minutes), $129[$1=110Yen](Japan, 1168 minutes)


Airwolf - Season 1: $25.99(US, 592 minutes), $91[$1=110Yen](Japan, 567 minutes)


So It is reasonable to buy them in US. But unfortunately the region code of DVDs differ between US and Japan. It means that I can't play them with Japanese DVD player or in Japan. Why aren't they the same?
And I think why they in Japan are expensive is that Japanese DVDs of American tv shows and movies have the translated Japanese dubbing and the superimpose. But is is worth to the difference that make the price several times of the original one?

By the way the region codes of Blu-ray discs in the both country are the same...