I'm finding if I leave wifi turned on during the day at work (not connected to any network) Google Play Service seems to chew battery and usually around 35% for the day. But if I disable wifi (leaving just 4G for internet connectivity) Google Play Services seems to be 5-6% for the day.
I wonder if it is continually searching for known wifi network (but doesnt find one, and therefore keeps Google Play Service awake... Not sure, but keen to see if anyone else shares the same experience with wifi on / off