Ice cream is always the dessert in TPAC Y (according to one FA, they sometimes have mousse but I have never seen it). I don't eat ice cream, and actually a lot of other people I know don't eat ice cream.
The in flight snack in Y on NRT-ORD flights (and others ex-NRT I assume) is basically exactly the same as AA (ham and cheese sandwich on a hamburger bun with a kit-kat and one of them has a second snack, but I forget who...).