Grad Students Not Plagued By Toxic Sushi Epidemic

Why, in an editorial about toxic tuna sushi, does the NYT feel obliged to explain why sushi is appealing? "New Yorkers have come to love the convenience, taste and aesthetic appeal of sushi." Imagine the same said of pizza. Isn't the fact that a food is readily available enough evidence that people like it? Is sushi-liking so improbable that it must be piece-by-piece (no pun intended) laid out?