Prepared food section has "no gluten ingredients" listed for every item that is gluten free. all sushi comes with gf soy sauce.
The most amazing GF selection of any grocery store I've ever been to, I absolutely 100% recommend...I just wish they had one closer to where I live now! If you go there for a meal, their pre-cooked food section also clearly marks food items not containing gluten. However, the signs always state that there are "no gluten ingredients" and imply that most of the food is prepared in shared prep areas. I've never gotten sick after eating there, but definitely something for those with high sensitivity to watch out for.