Is there a way to display the key for a metadata value in one place and the value in another?
It would be handy where e.g. locations have a short code to be able to use the code in a brief (asset) listing of events but the full name of the location in the event's own page.
I don't believe this is possible at the moment, no. You have to set which one (key or value) is returned on the front-end by the field. You could submit that as a feature request on the bug tracker though.