Account passwords are always saved, and I have no plans to change that.
If you really need irregular access to your mail, consider a web browser.
However:
- Passwords are stored in internal phone memory, not accessible unless the device is rooted.
- They're encrypted (btw, passwords stored by Android itself are supposedly not encrypted... I recall reading it somewhere, but haven't checked myself).
- The app has a "pin code" feature to lock down access (app settings -> security).
- Google recently rolled out a "where is my phone" service with a remote wipe capability... available for all devices with Google Play services, not just 4.3 (as one might think).
http://howto.cnet.com/8301-11310_39-57597521-285/find-your-lost-android-device-with-android-device-manager/