Last night I posted a copy of my iPad Summit presentation. The presentation was created in Google Slides. I forgot to share it as view only and instead only selected publish to the web in my settings. I have changed that setting so that now anyone who has a Google Account will be able to make a copy of the slides for themselves.
To make a copy of a Google Slides presentation that you find on the web, click on the gear icon and select “open editor.” When the editor opens (you’ll need to be signed into your Google Account) select “make copy” from the File menu.
The process is similar for Google Documents that have been shared as view only. That process is outlined here.