I disabled Google (the app itself) because at one point I figured "Google knows too much about me". So I went ahead and disabled it from the list of apps.
After this, the battery drain of Google Play Services has been immense. It drains my phone fast. I'm nothing if not a scientist, so I activated Google again and rebooted. I'd gone for two weeks without Google enabled.
Now my battery usage seems back to normal. I know the two might not be necessarily related, but the drain started around the time I disabled Google, and seems to have disappeared once I re-activated it.