Most of it's just trash... bottles and wrappers and stuff. But remember the time we brought home that whole pretzel? Sometimes the humans just throw away their food when it's still in its container.

[He knows his brother is fascinated by humans - heck, so is Leo, even if they make him nervous too. But he's not too worried about Raph's sudden interest; they've all heard the shuffling feet and low murmurings overhead while playing near storm drains in the warmer months. Master Splinter doesn't like them being so close to topside, but this would hardly be the first time they've done so.]