rmt_storage keeps polling and spam logcat
It's a bug in the Android build as near as we can figure.  If your device is rooted there's a workaround otherwise have fun charging your tablet every single night.  Check out this Google Groups thread about it.

On my Galaxy S4 I stopped the service and everything still worked.  However I found that after disabling wifi, I was unable to enable it again until I rebooted, even after restarting the service.  Obviously this is not the case with the Nexus 7 2013, but that does confirm that it's "modem" related.

However I've found several other threads online that reference this service as having to do with external SD Cards (in some ROM development threads) but I do know that with it stopped my S4 wasn't able to toggle the wifi state anymore.