Why does iCloud take up 30+ gigs of storage on my Mac? For some reason iCloud is taking up over 30 gigabytes of storage on my MacBook Air. How do I get rid of this? I though the whole point of iCloud was to save space not eat it up! I'm on macOS Sierra 10.2
Your iCloud Drive contents are cached. After looking over the new storage management features in Sierra, doesn't look like the "Optimize Storage" feature will clear that.

If you go to About this Mac > Storage > Manage > iCloud Drive are there options there to remove files locally? I don't use it personally so mine's empty.  :)