Q: Lack of subtitles on iTunes vs more subtitles on DVDs

Why do Apple sell far more movies and television shows on iTunes that have far less Closed Captions than if you bought them on DVD??

Sometimes a series of movies on iTunes would have one or two of them with CC but the other do not, for example on iTunes

For example: On iTunes, Spider-Man and Spider-Man 2 will have CC but Spider-Man 3 do not, same with Iron Man and Iron Man 2 have CC but Iron Man 3 do not.

Yet on DVDs, all three movies would have means of subtitles for the deaf, ALL in the series.

On iTunes, only Back to the Future do have CC but not the last 2, yet on DVDs, all of the triology would have subtitles for the Deaf.

Same for television series, for example the 1st series (known as seasons in American-English) of Red Dwarf (and again same for the second series/season) the first episode do not have CC but the rest do.

And other thing, most people used CAPS LOCK in email or discussion boards or in text messages, and gets told off that using caps lock is like shouting, yet some of the movies on iTunes have some of the CC in caps, examples being Jumpin Jack Flash, and When Worlds Collide. I found it annoying trying to read subtitles that were in caps letters for the whole movie.

Then there's the fact that most movies and television on iTunes seems to lack more subtitles for the deaf when compare to DVDs.

You could get Star Trek: The Original Series, Star Trek: Deep Space Nine, Star Trek: Voyager, need I go on...? with subtitles for the deaf on DVDs, but on iTunes, it seems so far, only ST:TNG Season 1 & 2 have CC, mind you I haven't downloaded them so I don't know if they're any good.

Disney's Planes as well as Cars which have subtitles for the deaf on DVDs, seems to have no subtitles on iTunes???

If downloads is supposed to be the future and DVDs is going to history books, how come downloads seems so backwards? Have Apple gave up the rights of the disabilies, including the deaf who needs more subtitles as well as proper subtitling (in that case of those iTunes movies that are in CAPS LOCK)!

I'm starting to think it was a mistake for me to use Apple, iTunes, and so on, well I got one good news for Apple, even if I can't enjoy movies on my first generation iPad, then they're lucky i'm not going to jump ship as I still use my iPad for a lot of work, but unless there are more subtitles for the deaf on the same level as DVDs, I'm going to stick with the good old DVDs!!

I don't understand why is there a lack of effort to add subtitles for the deaf on iTunes??