Why do I have to authorize my map-editor every time I open it?

I begrudgingly understand the lack of LAN and the default to "always-on" battle.net connection required to enjoy the single and multiplayer aspects of Starcraft II.

But why do I have to log in to use the editor? Sometimes the editor lets me 'map-edit' without an outside verification, but every so often (it seems almost randomly, to me) it forces me to "authenticate my account". What is the editor doing that mandates a connection to battle.net? Is this just Blizzard's DRM overextending its hand at my expense?

Is there anything I can do so I don't have to log-in every time I want to test and/or edit my map?

So, with the advent of patch 1.1, I discovered the real answer to this question.

When loading documents with Battle.net-only dependencies, you will now be prompted to log in >and download the dependency data, rather than failing to load.

So the reason you have to log in, as that the default map (or my default map at least) had some online dependencies that I didn't know about.

Legacy Answer:

From the Galaxy Editor FAQ on the Battle.net forums:

Do I have to authenticate to use [the editor]?

Yes! You need to authenticate the Editor once every time a new patch is released, other than that, you should not need to authenticate.

So apparently, starcraft 2 is patching a lot more often than I was aware of...

12. Duration of the “On-line” Component. The Game is capable of both offine and online player modes, both of which require that you obtain authorized access to the Service. You understand and agree that the Service is provided by Blizzard at its discretion and may be terminated or otherwise discontinued by Blizzard pursuant to the Terms of Use.

_{from the EULA (skip to page 11)}

You have to authorize your map-editor because you agreed to.