Yup they don't have their own individual greetings to begin with, they just use random generic stuff until you give them one for the first time.
When they ping for a greeting for the first time, the imput field is blank so you can write what you want. When they ping you for a second greeting, the input field has the last greeting that they were given still in it (which is handy for me because I hardly ever change what mine say lol).
Hope that helps anyway!