On both Leap 42.1 and Tumbleweed, when installing over USB, the 'installation
repo' (the repo linking to the installation media) is set to auto refresh

Screenshot from openQA - 

https://openqa.opensuse.org/tests/87245/modules/zypper_lr/steps/4

This means that as soon as a user removes the USB and does anything with yast
or zypper, it asks for the USB to be added again - this is a real pain, and
causes lots of confusion for new users.

When installing over DVD-ROM, the installation repo is not set to auto refresh

Screenshot from openQA 

https://openqa.opensuse.org/tests/87244/modules/zypper_lr/steps/4

I have checked on SLE 12 SP1, and on there the install repo from a USB install
is also NOT set to Auto Refresh

EXPECTED BEHAVIOUR

USB installs should ask like DVD installs, the install repo should not be set
to auto refresh