All batteries slowly drain after being charged, even when not in use. That being said, the Buds are in always low energy Bluetooth mode to more quickly pair/connect to devices and emitting UWB (ultra-wideband) frequencies, should you lose your Buds. You don't actually want to ever turn the Buds completely "off."
I agree, and since they don't drain the battery that bad, I usually have them on the case. Also, the case works even without charge, and they remain "off" while in the case. I can testify that it's convenient that they don't shutdown since finding them can be a hassle, specially if they are the black ones.
