above: a miduradroni, in its first (but not final) appearance in the popular cartoon reality.
The fictional universe of the Simpsons is depicted as a "cartoon", but it is not a "cartoon reality". Though there are numerous fantastical or surreal elements, the world itself is not distorted to such a fantastical or surreal extent as Dragonball Z or Looney Tunes. The citizens of Springfield are drawn as cartoons, but we can still imagine their bodies as being similar to ours.
"Itchy and Scratchy" is, furthermore, a cartoon inside the Simpsons wirkd. To the viewer, both Scratchy and Bart are drawn in the same style. Nonetheless, the citizens of Springfield see themselves as "real", while recognizing Itchy and Scratchy as "cartoon characters".
Itchy and Scratchy is also a very violent cartoon... and because we (audience) see the Simpsons and Itchy/Scratchy as the "same level of cartoon", the violence is partially realistic, and thus framed as more disturbing in our eyes. In our world, photorealistic animation depicting disembowlment is not broadcast for wide media consumption.
And back to the subject at hand... besides just other Simpsons media (i.e video games, comics), there are Simpsons toys, clothes. They are not "just" a cartoon anymore; they've permeated into the physical world quite a bit.