Thanks a lot for the detailed explanation. If I understand it correctly, there is no way to really prevent these Apps from “running” in the background, although “running” just means they sit idle in memory 99.9% of time and don’t do anything unless a broadcast event they are subscribed to gets fired and then they are permitted to do small task.
So I guess the most likely issue is that either something else on the phone is causing this drain or that some App constantly gets restarted (which is expensive) for some reason instead of just staying idle in memory.