2. A few people cry out Hear, Hear! before they begin a wine toast. What does that cry mean?
3. News used to be read aloud in town squares so that all could hear it. Town crier would call out "Hear Ye, Hear Ye" to make sure everybody was paying attention. So, calling out "Hear Hear" before beginning a toast, is used to attract the guests' attention based on that historical matter.
4. In the 1700s, when the government in Britain was gaining more power from the Monarchy, the noise in the chambers could become overwhelming. So when a member of parliament would begin to talk, his friends would call out "Hear Him! Hear Him!" to shout their approval of his message, to encourage him to keep going. This soon became shortened to “Hear Hear!” to be interjected at key moments to keep the momentum of the speech going.
5. If you're showing your approval, the call is quite appropriate when someone is giving a toast!