I have noticed, both on the Ratatouille soundtrack and the WALL-E soundtrack, that two tracks sound strangely alike. For Ratatouille, it’s “End Creditouilles” and “Colette Shows Him Le Ropes” For WALL-E, it’s “Define Dancing” and “EVE”. Why?
They’re similar because they’re trying to create a similar feeling in their respective scenes.
Yep, martini nailed it. Movies have similar musical cues throughout when they want to evoke similar emotions. The EVE and Define Dancing tracks both have a kind of majestic, beautiful, and even thoughtful feeling running throughout them, because both of those scenes should evoke those same emotions.
and because both are written by Peter Gabriel. And there’s another cue, i don’t remember which, where the “Down to Earth” intro can be heard.
In Ratatouille I think that the end credits’ track resume all the tracks, only rearranged.
ok.
Define Dancing and Eve were written by Thomas Newman, with some input from Peter Gabriel on the arrangement.
The music from Down to Earth was also by Thomas Newman, with Peter Gabriel doing the lyrics and such.
yes, Peter Gabriel AND Thomas Newman 
Peter Gabriel is credited as composer, not just arranger, for “EVE” and “Define Dancing”, isn’t it?
In the interviews that I recall it doesn’t seem like Peter Gabriel had a lot of input on the score cues. The song seems to be the notable contribution he made (which was also co-written).
My main objection was the comment that the two cues were written by Peter Gabriel.
What martini said. It’s like on the Finding Nemo soundtrack there are bits that are repeated almost exactly so that a similar feeling can be…um, felt. 
like 72 Degress and Sunny and March of the Gels were very similar.