Without ritual, it's nothing more than an abstraction. One of the functions of ritual is to enhance group identification, though I think Ahad HaAm was referring to more than that in his remark. Ritual serves other purposes too. We are influenced by the rituals that we practice. Psychologists have shown that the way we act influences the way we think.
Some rituals aim to purify our character.
By observing them, we learn how to become better human beings. Others teach us about the holiness of different things, such as the value that Judaism places on human life. Prager and Telushkin examine these and other reasons for rituals in their 9 Questions People Ask about Judaism. It's worth reading to see how they talk about the different functions served by the laws of kashrut. While many liberal Jews may feel differently, traditional Judaism says that the purpose of Jewry is more than just to better the lives of individual Jews.