If you wish them 'Bonjour' they would invariably respond and also salute.
"Bonjour, Mademoiselle," we replied; and looked round for the shop-keeper.
"Bonjour, Monsieur," she said in her fluent anglicized French.
Then, returning to the path, shakes hands with her, says “Bonjour!”
When he was in a thoroughly good humor, he would often say, "Bonjour, madame!"