People are great at pattern recognition. This has proven to be extremely useful to our species, but we also have a tendency to see patterns where none exist. We tend to seek these patterns in random information to create explanations to support notions about gambling and luck, religion, paranormal phenomena and so on.
These patterns often depend on culture.
Radical Cartography has a neat section showing the night sky. You can overlay the patterns for the Chinese sky, the ancient Greek sky and the current Western sky. I'm sure there are many hundreds of other cultures with their own interpretations.