Remember that people used to bathe only on Saturday night, and often then the water was shared with family members. Who got the water first was a big deal. Today, the ads have told us we need to use soaps and shampoos every day. Once when camping at a state park during a drought, the bathrooms did offer showers (a mistake), but the walls had big signs begging people not to use much water because of the drought. Some teenagers were there, and the girls, oblivious to the signs, all took morning showers and shampooed their hair, thoughtlessly using huge amounts of water for no real reason other than having been trained by endless TV ads. This to me is NOT a camping trip. 

I, too, used to take long hot showers every day, but no longer. The amazing thing is that my skin is so much healthier- not dried out the way it used to be. Save money on all those oils meant to undo the damage to skin by excessive bathing. And some say your body absorbs Vitamin D, critical for health, when you allow your skin oil that has been exposed to the sun to remain on your skin for at least 8 hours to absorb and not soap it away at night.  Here is the answer to the question people are too embarrassed to ask- I shower about three times a week now.