Who wouldn't have an obsession with the PB&J? I mean, honestly...it's perfect. The mix of sweetness with buttery saltiness. The ease of making it. Toasted vs non-toasted. Crusts on vs crusts off. Cut in triangles or in half or eaten uncut. So much variety. Do you go with generic Welch's concord grape? With a higher end grape jelly? Mix it up with blackberry jam or strawberry jam? Chunky vs smooth peanut butter?
Plus, its the only sandwich my 8 year old will consistently eat in her school lunch, so there's that.