"Traditions are solutions for which we have forgotten the problems" - I think this quote fits to so many more situations as I get older. Relationships (w/ friends and family) are easily strengthened by traditions.

Traditions are very algorithmic. Traditions sometimes force us to connect/meet people and resolve conflicts if you follow the "rules". Traditions can be hard to follow (as in overcoming some inertia or discomfort).

PS: Don't have to think of just cultural traditions. A gang of college friends can have their own silly but decades long traditions and inside-jokes.