As exotic as kanji (Sino-Japanese logographs) may appear to the uninitiated, most of those we encounter in everyday situations are intended to convey notices and other mundane or essential information, such as 禁煙 kin'en (no smoking) or 駅長室 (ekichō-shitsu, stationmaster's office).
But as one's comprehension of kanji grows, so does awareness of the historical and cultural baggage its characters bring with them.
From a character's style, some readers will know at a glance the era in which it was created and its purpose. And from that point, you become not only a reader but a history buff and art critic.