Why do many anime OPs and EDs have onscreen lyrics? I have noticed that much, but by no means all, of the anime that I've seen has had lyrics onscreen during either its OPs, EDs, or both. Why is this so?

I know karaoke is fairly popular in Japan, so do people actually sing along while they wait for their shows to start? Perhaps it is done to promote the songs licensed for the openings/endings? 

Some examples of what I'm talking about include:


Shirokuma Cafe


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Pokémon


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Dragonball Kai


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Doraemon



Note: Emphasis mine in all of these images.

As a bonus if you could include some information on these side issues, that'd be great:


Is this exclusive to anime, or does it appear in other forms of Japanese media (e.g. music videos? OPs of live action dramas? etc.) 
Why are they almost never included in licensed English versions?
What was the first anime to include them?


Perhaps this is a slightly broad question, but I assume there must be some general consensus on the matter. Does anyone have an explanation for this phenomenon? :)
I think this is only common among shows aimed at children. All of the examples you gave were shows which are, at least partly, aimed at children. Having karaoke for the song helps the younger viewers sing along, and also has some educational benefits in terms of learning more advanced characters. If you watch anime targeted at older viewers, they rarely have karaoke.

It's also notable that those anime aimed at younger children are using only very common kanji that even children would probably know, and is giving furigana. Those aimed at older children tend to have more complex kanji and sometimes omit the furigana as well. This isn't apparent from just the exam