In the past year, United has made more mistakes in my favor than against my favor. That said, it's not accurate to say that it all works out in the end. Therefore, every time I see miles in my account that should not be there, I cal UA and let the burden be on their shoulders. It's never been too hard to chase down. And whenever I am owed miles, I usually get them within days, if not minutes.

When it comes to upgrade vouchers, I will never understand the pyschology on FT! After all, the airline has already given us the free upgrade. And yet so often we want two upgrades (in other words, we want them not to remove the free coupon so we can use it in the future). Doesn't make sense to me.

So, in my not so humble point of view, I do think it is unethical to use the coupon. I would mail it back with a note saying, "Perhaps a charity can use it."