Cross-Cultural: Differing Rites of Passage

I am using my sociological imagination to examine how rites of passage in cultures are not all the same. I am a firm believer that geographical location determines a lot of things for people. For example, religion, clothing style, and as I mentioned in my first post, a person's choice in beverage temperature.
Coming from a different culture. (Laotian culture) I have always been interested in cross-cultural comparisons. One comparison that always amazed me was how American people view 18 year olds as adults. In my own culture, an 18 year old is still a child who will usually live under their parent's roof until they're married off. However, one interesting thing I learned from an American friend of mine, is that some parents give their child a bill to pay when they get to this age. This rite of passage does not exists in my own culture. Lao parents typically try to take care of their child financially until they are married and have their own job. The reason for this is because our parents do not want to burden us while we are trying to study and further our future. I found it crazy that my friend had to pay his water bill for his family. I understand the practicality behind having my friend pay his family's water bill, but it made me realize how rites of passage vary so much between cultures. There are definitely differing rites of passage throughout the world, and it is interesting how something that can seem so natural to someone else can come as a shock to others.