You are entitled to your biases or whatever it is.
We shower each day and we do cook but not all meals.
Laundry not unless we are n sewer.
Gray tank is 60 ga3llons, I think. Fresh water is 100 gallons and black 40 gallons.
Actual number of days with just showers, I'm not certain as we seldom dry camp. Let's say 15 gallons x2 x 2 days. But actually we probably get 3 days and maybe 4 sometimes.Depends if we do dishes I suppose. Sailor showers, do it a few time if dry camping but we don't do that much. We like to enjoy the stay wherever we are and that means showers and washing clothes as needed not taking time out of enjoying things to go to a laundry with rolls of quarters. And with age and bad back pulling up every three days or whatever and the waiting in lien and the routine of draining and FLUSHING taking an hour or two at least the times we did it welll.... I'm not RVing for work and sometimes intolerant me me people or anyone else who don't want to spend time at the dump either. Maybe you have a Prevost with 260 gallon gray/black tank and 260 gallons fresh water. Next coach will have the sewer and electric and water on reels but I'm still going to eschew dump station only parks. Some parks fun by Parks Canada well you wash among the skeeters, and no soap in the lake or run 100 ft of hose and only a dump stations and spaces for small towables. Still we have done it but now I'm not going to/not able to.
You enjoy the dump station life and working or maintenance on a vacation or full timing, more power to you.