there is a sancticty, a Kedushah to the Bais Ha Knesses that derives from the Bais Ha Mikdosh. There are numerous Halachos that dictate proper conduct and AWE.
This is the way the Jewish People, Avdei Hashem, the kingdom of priests that we truly are, have always conducted themselves.
Yes the Bais HaKnesses has also been a place for the community to get together and discuss community problems, needs, and to fast in times of need. and for Mitvahs and sometimes the associated Seudas.
But it NOT a social hall to get to together to shmooze and party. At least not until america, where many have learned the meaning of the Shul from goyish attitudes, subconsciously of course