Yes – unless you change that in OSMC’s os.json.
If you grab all the files, you can effectively create a NOOBS install locally (I know OSMC is fetched online at the moment).
Some helpful resources:
http://download.osmc.tv/installers/noobs/
If you take a look at how Raspbian is set up (it’s bundled on the SD already) and its directory structure, you may be able to work out how OSMC should be packaged on the SD. You could then edit our partitions-pi*.json and fix things up to your liking.
Let me know if you need some pointers. I’ll have a chat with the NOOBS maintainer and see if something can be done. I know that add-ons and large libraries take a bit of space, but, conversely, we don’t want to consume space unnecessarily that some users may never use, and we like to fit on some smaller (4GB) cards.
As an aside, I believe you also posted on the Raspberry Pi forum. If you find this solution satisfactory, I’d appreciate a link to it from the Pi forum as I am sure that other users will stumble upon this problem.
Best
Sam