i have goose down duvets for all of my rooms, and I absolutely love them. They're cool in summer and warm in winter. And yes, they're light as....you guessed!
Easily the sexiest covers I've ever owned.
I compliment you on both your taste, and your patience.
There is always someone who does not "get it". They want hotel service, including acres of Wabasso. Home hospitality is out the window.
And the fact that they complained after the fact speaks volumes. My sister had an apt description not fit for print here along the lines of No F'ing Class.
I would include the fact you offer such a lovely luxury to your guests in my description. It is a thoughtful gesture. If they want a top sheet, simply have a folded one next to the towels.
Cheers1