It's not about just what the user can do with a replaceable battery, it's about how much easier it becomes for the company to replace batteries in the field (an

It's not about just what the user can do with a replaceable battery, it's about how much easier it becomes for the company to replace batteries in the field (and backplate, if too thin): just ship new batteries and have user come and immediately leave with a "fixed" phone. (Of course, if your new battery is also broken, then nothing really can help.) And — do correct me if I'm wrong — but removable batteries don't add thickness, only length.