It's happened to me twice now, with binoculars. When I'm observing a town from afar with binoculars I use that time to make sure I'm hydrated and energized.

Well, cutting to the chase - when I use the option "Eat All" on something like say a zucchini (what it happened with last time) and the second the action is finished enough to put something (the binoculars) back in my hands I pull up the binoculars again immediately, they're zoomed in and all seems well. That is, until maybe 5-10 seconds later I see the final "You have finished eating all the zucchini" message then BAM - my binoculars disappears from your inventory as if I'd eaten them instead of the zucchini.

I suppose the only good news is you'll still have that zucchini so you can eat it one more time.

This has happened to me twice both times while using binoculars. I'll keep trying to reproduce with other items I don't mind losing and will report back if I manage to have this happen for anything else, and I'll try something other than the zucchini + binocular combo. Oddly though, that's what I was eating/using both times.