Okay, here is probably a foolish question...
I just got a new Kobo WiFi - a replacement for a previous one.
I also have an original Kobo and a Sony 650.
I mostly buy from Kobobooks, download the file from there and open with ADE.
Then I add the book through Calibre and send to device.
I don't use the Kobo desktop at all.
All my books are DRM-free and saved on my secondary hard drive.
My question is this: Do I still need to authorize my Kobo with ADE?
I guess I don't really understand ADE's role in all this.

If I don't have any DRM-ed books do I still need ADE's approval of my hardware?
Are there advantages to ADE that I'm not understanding?
And now I have a secondary question.

Is there any reason to launch the Kobo desktop when I first plug in the new Kobo?