Japanese like to eat sea weed. Especially, wakame sea weed makes a typical miso soup ingredient. A sheet of nori sea weed is always used for sushi roll.
The word ‘weed’ sounds too bad. Japanese eat it more like vegetables. Sea weed or sea vegetables are rich in minerals and healthy!
Mozuku vinegar is slimy and looks less pretty. But if you are curious and health-conscious, it could be worth trying.