Not much. Its the route and then the idling. As haseeb said it consumes like crazy when on idle.
See the transmission in current 1.6 altis is the same which was used in 2011 to 2013/14 wali corolla auto and altis cruisetronic etx. Its a 4speed auto transmission and will dor sure consume more.
I owned an altis cruisetronic 2012 se 2017 it never crossed 8.5 without ac in karachi and my routes are smaller. Once on long it did cross 12 mark but that was a non stop drive from karachi to Hyderabad.
If 1.6 had a cvt transmission then it would've been an ideal thing but that is being provided in grande and cruisetronic right now