It's frustrating, but it's just one of those things that you can't do too much about. I've asked people to let me know when their items have arrive safely, and I guess something that I sort of hope comes with that is an implicit mindfulness in relation to some level of renewed contact when the item does arrive... otherwise I don't really feel as if I can do too much.
Huh... a feedback coupon. I like that idea, that could work!
I guess a feedback request, if stated properly, could be a done too. If I was careful in how I phrased it, that's something that I could see myself toying with at some point.