Originally Posted by
Wexflyer
Aren't there? I am not a US citizen. Whenever I exit the US they always look for some evidence of legal presence when they look at my passport. If my friend were to travel on her EU passport, they would not find any evidence of US entry/legal presence, as of course she used her expired US passport when she last rentered the US.
The airline is looking for your entry card because they need to collect and submit it - but they are not immigration inspectors and have no authority, so it's not an exit control because they cannot stop you from exiting if you have a valid passport and entry docs for your next destination.