I get the reasoning, I just don't care for that excuse. I would have preferred to have it all in my season set, I shouldn't have to buy the same episodes just for the extras.
It's not really an "excuse," it's a fact of economics. The extras wouldn't be produced if it weren't for the separate release. They have neither the funds to produce the extra material nor the space in the set for another 30 minute feature.
So you wouldn't have the option of having both the complete season and the episode-specific features. If you'd rather them just cut out the separate release all together then you simply wouldn't have the extras that would come with it either.
You don't "have to buy the same episodes just for the extras." You're the consumer. You make the choice of what you buy or not. If you don't want to buy both, then don't buy both. It's as simple as that.
You're right, to rephrase it, I think it's unfortunate that one's only option to have both the features is to purchase the two sets. Whatever the reasoning behind it
, I still think it's rather crummy that you can't get them in just one set. That's all I've been expressing.