It's also worth pointing out that, as a member of EFTA (European Free Trade Association) Iceland is a member of what is termed the EEA (European Economic Area). The EEA covers the nations of the EU and EFTA and allows for free movement of labour.
With reference to Air Atlanta's non-european crewmembers, while it is true that they employ a large number of Americans and Aussies (among other nationalities) Atlanta has bases of operation outside of Europe as well as inside, for example Jeddah.
With the application of JARs, Atlanta are employing ever more European nationals. Given that Iceland has a population of less than three hundred thousand people it should also be seen as an encouraging sign that the bigger Atlanta grows, the more non-Icelandic Europeans they will employ.