I'll start off with: The Batter status page lies or at least some of it.
Next, this is not only on our AF2 but mostly on all MM devices with minimal changes on AOSP build.
Now, 3 things can affect this:
Wifi advanced settings
Google Play Services
As for the Advanced settings on wifi, it is what @hopialikeit mentioned, the "Keep wifi on during sleep"
As for the Location settings, it has something to do with Scanning (see image)
although others may argue that it should be showing GPS instead of WiFi or Bluetooth should be shown as well. I've always had my GPS on but never have I seen it appear on the main Battery status page though it does when you tap on the graph for a much detailed look
not mine since I don't have data on my phone to share SS
Lastly, as always, on which battery drain will really occur is the Google Play Services, so any Google service you've used while on WiFi will register on the Battery status page as part of WiFi even if it is not really the WiFi driver, except 3rd-party apps that also uses WiFi. And we cannot kill Play Services normally. Anyone saw Google Play Store/Services appear on that page? I doubt. LOL
Sharing this information based on what I've had so far using my rooted AF2 with Xposed+Greenify+Amplify set in comparison to stock image of my AF2 usage. The rooted one does not give the same information on those screenshots shared by @tonmoydas.phy
EDIT: just because I rooted mine and was able to get a different result means that anyone can eagerly root theirs, I'm not stopping you but at least know what it is and what it is for that you are doing it.