Ive realised bamboo kendamas have a lighter and darker toned stripes. Are those just the grain or they are strips of bamboo connected tgt?
The light/dark striped bamboo kendama that I've seen are laminated segments of bamboo (stuck together pieces). Since bamboo is mostly hollow, unlike regular trees, you can't really make a kendama out of a single piece so they glue pieces together like many of the other multiwood kendamas out there. There is a "solid" bamboo sold by a couple of companies but I believe it's more of a "particle board" construction made of bamboo chips/sawdust and mixed with a binding compound. They're really heavy too, the samples I've seen are often 200g+.
@goenKendama is correct, bamboo kens are made out of a laminate. You can get that laminate made with all the same colour of bamboo, but the 2-tone design looks nicer so it's more popular