I agree; I don't think it would occur to Joseph, on his own, that disappearing would hurt his family. But I felt like Rose should point it out to him - it frustrated me that her big request was "Always become a specific chair," rather than asking him to stay.

I think she felt she didn't have the right to ask. But I don't understand why not.

The binoculars bit was adorable. But it's probably just as well he didn't cook for her! Who knows what she would have found out? I think they managed to create their weirdly sweet relationship because there was this distance between them - unlike between Rose and her mother, who crowded her (even leaving out all that unplanned emotional sharing in meals).