Yup exactly. Your use of the word "entire" is what is wrong with your thinking, and what every other package manager gets wrong too. There is so much duplicated code out there as a result of people thinking to themselves "this is too small to be its own component". Instead, they just copy-paste it into the bottom of the file.

Yes the "on-escape" component just attaches an escape handler to the document. One of the reasons for it is just to not have to write that code yet another time, since doing that is boring and, more importantly, prone to bugs.

But the other reason is that it turns this:

  document.attachEventListener('escape', fn, false);

into this:

  onEscape(fn);

without losing any clarity whatsoever.

It's also more performant than attaching tons of different escape handlers, because across all components everyone will share the same event listener. Even for components that somebody else wrote and you're just using.

So yes, there's a component just for onEscape.