iPhone using too much data for system services

This month system services used 465MB, of which I tracked down Software Updates as the biggest culprit at 341MB. Still push notifications (57.2) and Time & Location (19.6) each use way more data than they should, given my phone is on wifi 95% of the time.

I hadn't even realized that Automatic Updates would go ahead and download over cellular unless you turn them off completely - the latest update was over 1 GB so I guess I'm lucky only a third of that happened over cellular? I'm on pay as you go, with 250MB included each month, but I'm not accounting for random huge updates like this. Over this, it comes out of the booster data, which is $30/GB, so that update cost me $10.

On top of this, the times I'm getting cellular data incurred according to my provider is often at times when my phone is definitely in the house connected to wifi, like from 12am to 7am - what gives? Why keep using data when wifi is available? The last two nights alone after midnight used 30MB - more than 10% of my monthly amount, for absolutely no reason.

Overall Apple just doesn't respect the data they are voraciously consuming and the money it costs their customers. I for one don't want to pay more than the $15 a month on my plan plus *reasonable* usage of my booster. I understand if I use Waze in the car it will take some data for instance, and that may cause me to go into my booster. As it stands I'm going to start turning off cellular data until I need to consciously use it - which is a pain. I've already turned off so many apps under the cellular section, turned off background use for more, this is just insane the way I have to hobble my device just to prevent Apple sucking away my data for no reason.