Kombu for dashi.. cook's treat?

I have a question about making dashi. I make dashi with some regularity, and I put the kombu & bonito in the freezer to make niban dashi, and this makes me happy to be getting good use from these ingredients. I've also seen recipes where kombu is a main vegetable ingredient. Now, in western cooking, recipes often ask you to make some good stock with, say, carrots & celery & onions, and then they suggest that you throw away these vegetables and put new veggies in your soup. Well, I've learned to always savor those boiled-to-death veggies as a cook's treat, or just as lunch on the soup/stock-making day. I love them with a little salt & maybe a bit of butter or olive oil. Not fancy, but comforting everyday food. So, I wonder if Japanese cooks use the kombu from making niban dashi for anything like this, a sort of cook's treat or plain home food?
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