Food is an artifact type. Even though it appears on some creatures, it's never a creature type.

You can't sacrifice a Food to pay multiple costs. For example, you can't sacrifice a Food token to activate its own ability and also to activate Maraleaf Rider's ability.

Whatever you do, don't eat the delicious cards.

You must remain in your seat while looking around the room. No, you can't pick up your seat and walk around to get more Food.

Trash cans are receptacles whose main purpose is storing garbage. They are often lined with garbage bags. A bag by itself isn't a trash can. A can isn't a trash can if storing garbage is not its primary purpose, even if it contains trash (e.g. a soda can with gum wrappers inside).

You can't bring your own trash cans. They must be native to the room you're in.