Good suggestion. People sometimes think of the MO as Beis Hillel and charedim as Beis Shammai. Not sure if that make sense, but regardless, in Pirkei Avos, Shammai said “Receive each person with a cheerful countenance.” In other words, if you want to be truly frum then you better smile at everybody! (In Avos Rav Ishmael also says “Receive each person with simcha” — another way of saying the same thing).