"You say good morning."
I have an objection about that too, and I do think I have made a note about it in the incubator. English people may do use "wish" sometimes, but in greek it just sounds weird, at least in this particular case. You could say "Εύχομαι να έχεις μια καλή νύχτα", but "Εύχομαι καληνύχτα"? Eh. :/
Αs a native speaker, it seems to me different phrases. Καληνύχτα is a salutation, as it is "Good morning". Yes, it is literally a wish, as most of salutations. But it is so common, that almost never heard "εύχομαι καλημέρα", it is the same case as καληνύχτα. I asked some other Greeks too about and they agreed with me, if you are interested in. Try the same, Dimitra956826, to make a poll about :) Any other native Greek speaker around?
Ι have in mind Yiannis Ritsos' phrase: "Με τόσα φύλλα σου γνέφει ο ήλιος καλημέρα" (γνέφω=http://www.wordreference.com/gren/%CE%B3%CE%BD%CE%AD%CF%86%CF%89 ), in the famous song: https://www.youtube.com/watch?v=OW8YZNMz4r0 .But not a wish :)