Those figures are given by ARAI after running the vehicles in test conditions. In day to day use, expect 65-80kpl of mileage for a 100-110cc bike, depending on riding style and weight (pillion rider)
I don't know about other bikes of similar capacity but mileage of the bikes me or anyone in my family owned are written below:
1990 2 stroke bajaj chetak scooter : still returns 50-51 kpl
2006 bajaj CT100 : 76-82 kpl (lowest 68, highest 85)
2007 bajaj pulsar 150 dtsi : 52-56 kpl
2011 yamaha FZ-S : 39-46 kpl (lowest 27, highest 52)
2013 CBR250R : 28-34 kpl