BINGO. I won't get started on this, but there is a LOT that can be said for the exclusive and "high valued" premium cabins of internationally based airlines when you can look at the seat-map 1 hour before the flight and know there will be empty seats, that the only passengers you will be sharing your space with will be those that either a)upgraded from an expensive coach fare b)bought the ticket with miles/money c) have status with the airline and were upgraded (though this is very rare internationally IME).

Ill say it again though, this isnt a Delta problem, its a US-based airline problem.

I have not, nor will I ever, have a problem with employees traveling for free. Its placing them in premium cabins that I do not agree with.