CC requires a networking connection to add books to its database. It is (currently) not able to handle books dropped onto the device by calibre. I have been considering adding this capability, but some complexities and other demands on my time have gotten in the way.
The method eschwartz suggested will work: turn your laptop into an access point. There are several ways to do that, depending on the OS and how much tinkering you are willing to do.
My preferred method is to get an access point/router dongle and let it deal with it. I have a
Asus WL-330NUL but there are a zillion others available. The advantages are many: ease of setup, private wifi networks (what you would use in this case), wifi sharing in hotels, cable-to-wifi routing, and the like.
If you have a device with a cellular connection then you could turn on "Tethering" (a wifi hotspot). This should let both your laptop and your N7 connect and then talk to each other. I have used this scheme with both a Galaxy Nexus and a Nexus 5.
Finally, it appears that your N7/2013 model supports being a hotspot. See
https://support.google.com/nexus/answer/2812516?hl=en. If this works (I can't test it because I have an N7/2012) then it should suffice to turn on the hotspot, connect the laptop to it, then run calibre and CC.
EDIT: another thing you could do (which I and many others do) is to put your entire library into CC. I know of a few with 10,000 books in CC, and one with 18,000.