Maybe you could take a pre packed lunch? Saves money and you know what your eating..I'm all for a pre packed picnic

And you can eat sushi, you just need to know its fresh, ask them questions about when they have made it etc, google it you will find some information on it..
In the end its up to you what you eat from anywhere, I would often have asian food from food courts, not for any reason but coz i liked it ..And i was very careful of what i consumed ..