I did bird baths when I was living in a van. I would let a bucket of water warm up in the sun during the day then in the shadow of darkness I could do my bird bath. Wet body, apply soap then use remaining water for a good rinse.
Sure, on rare occasion it seems adequate when emergency forces you to leave home quickly or perhaps you are ill or due to post-op situation. I generally shower at least once a day, and often twice.
