Also, I've seen shows aimed towards kids using well-structured dialogue (Avatar, Marvel cartoons, etc.), so the problem lies with the way the dialogue in the anime was structured in the Japanese version.
You have to remember, your examples given were developed by Viacom on both commission (Many Marvel cartoons) and own titling (Avatar). These are English based animations, and not originated in Japanese. Normally, large scale companies have well-equipped translation teams able to read from the original transcripts of a foreign animation (example: Pokemon) and translate them. That is fine, then the translated dialogs go through what the far east actually calls, 'Culture Clips'.
A 'Culture Clip' is effectively the clippings or rough edging between cultures. What is allowed in one place might not be allowed in another and as a result, changes are made. Naturally, animation companies from the east have access as well as usage of certain resources the west doesn't (example: music rights or original transcript protection) which causes the western studios (the ones who dub the series in question) to modify episodes to fit the time slot needed and if having to, edit and every have content rearranged to fit the need.
On the topic of Pokemon seasons in the past, 4kids was infamous for their dubbing world. Like
Garchomp stated, they really pushed the whole pokeshipping role since the original dubs felt they were too underwhelming or not up to par with US animation standards. They wanted to have kids watch their show, and not get bored with it, so modifying the dialog and giving engaging parts to a viewer who would get hooked.
In all honestly as well, with the exception of your first pic linked, the other two do make sense when spoken.
"
Just because you're correct, doesn't mean you're right." is actually a good example here. When you look at it, some might feel this is a garbled statement, but in actual context; its correct in what it means. If you are doing something that you think is correct, it doesn't in fact mean what you are doing is the right thing to do. It makes sense as does the second statement.
"
When you have a birthday, you celebrate being born." This makes sense. Why do you have a birthday? To celebrate the day you were born. Its not incorrect or mistranslated. Its actually spoken correctly, a direct translation from Japanese to English. Sure, some can argue that they could of cleaned it up with better sentence structuring, but in all honestly; doing that would mean you are editing the original dialog of the transcript and like said before this in some cases (many in fact) is actually prohibited in the west.