Great point. Also imagine the space you save by not having a user serviceable battery compartment. No latches and contacts in a little plastic housing and wall

Great point. Also imagine the space you save by not having a user serviceable battery compartment. No latches and contacts in a little plastic housing and walls to separate the battery from the rest of the device. You can make it any shape you want and fill the entire device. I don't think giving away those benefits are really very worthwhile in any device I own. That includes everything from my toothbrush to my laptop.