Sometimes you don't know a kid's interests, and their gender is the best heuristic available (and a pretty good one at that). Obviously if it's e.g. my daughte

Sometimes you don't know a kid's interests, and their gender is the best heuristic available (and a pretty good one at that). Obviously if it's e.g. my daughter and I know she likes trains she's going to get trains, but not everyone buying a toy for a kid has that much information.