i just started working as a server at a restaurant that sells thai food
and has a sushi bar. from what i was told, everytime i sell sushi, i
must give 10% of the sushi bill to the itamae.

for example, if i had a lot of sushi orders, and it came to $100, i
would give $10 to the itamae. but what if the customer tipped me 15%?
which come to $15. that means i would have $5, but the itamae would
have $10. is that normal etiquette?

is that how other sushi places do this?