I think coming of age ceremonies are common in a lot of religions. It involves greater responsibilities in tribal cultures, and much more. As such, it is great cause for celebration. We Hindus, in private home ceremony, celebrate this one with the first sari, and in many communities it may be a quite expensive one at that.
I have no idea why other cultures often describe cultures other than the one they're familiar with as 'weird'. I guess it's normal, but I find 'weird' a bit derogatory. It's good to see it going both directions, from afar. Then you get a better handle on the bigger picture.