In other words, it's not too heavy, bulky, or expensive to include in my big kit.
It takes 16 drops of bleach to disinfect 1 gallon of water. There are 600 drops of bleach per ounce. A small, 2-ounce dropper bottle of bleach can treat 75 gallons of water.
I prefer to filter, but carry a dropper bottle of bleach (and a metal cup) as a backup. The best container is a small, dark-colored bottle with an eye-dropper top, such as you get from the pharmacy with children's medicine. My pharmacist was happy to sell me a new one for $3.00 when I picked-up other prescriptions.