I'm sorry, I really don't want to break your bubble, but if your travel is being paid with federal funding, you DON'T get to go first class. If you work for the federal government, you don't even get a choice of airlines. In fact, in this time of budget sequestration, you'd be lucky to be allowed to go anywhere with federal funding.
Signed, a sad scientist who hasn't been to a scientific conference in over two years.
How ‘bout I get a pony instead?