Save at least one empty packet from your pet’s dry food and use it to take sufficient kibble with you on a day trip or a weekend away. This way the food will maintain its freshness outside of your kitchen. This way you can throw away the bag and not have to bring nothing home to wash.
If your cat loves to drink water from a running tap, consider getting a drinking fountain for her. Cats in the wild drink running water and a pet drinking fountain recreates this in the home.