Edits create a new image.
So you are using the later version that has those much improved features, to create new images.
I really don't get what's so difficult about this for you to grasp. Either you are trolling or just refusing to understand what we are trying to say.
If I open a layered TIFF or PSD - file, do some work on it and save it, it's not a new image, it's the same image which I'm working on. I'm not exporting nearly all the images that I work on to "a final and baked form" eg. jpg or equivalent.
Now if I use CC version of say Photoshop to create the file, use the latest and greatest techniques available, they won't open in "legacy" versions of Photoshop if I cancel my subscription.
Is this scenario clear enough for you?
Edit: On top of that, if you are a new customer and go with the CC subscription, you won't even have a version to fall back to.