The point is the sink in the bathroom is normally over cabinets. If those cabinets are somewhere else, they still take up square footage in the RV, whether they have a sink or not. Losing the sink to gain square footage for the larger shower means losing the cabinet under it, that's all.

I'm just saying you may simply not understand the tastes and privacy desires of other RV buyers. They are putting those sinks in there for somebody. In spite of what you say, many people feel that living in a 23 foot rv with somebody increases the desire for rare privacy. I'm not saying it's rational, but it's the way some people are.

You should not assume your ass works the same way as everybody else's, either. When you assume, you say the ass of u is the same as me.

Manufacturers of RVs can't make a recycling shower if it has health risks even for a tiny fraction of the users. Liability rules will not let that easily happen. Reclaiming the water is a good idea but it is not likely to be just a filter. And it need not be, since it need not be fast. One can design a water tank, for example, with a rubber bladder in it so it holds two types of water (gray and reclaimed) and slowly reclaims water from the gray bladder which shrinks and puts into into the reclaimed. I imagine it might even be possible to have 3 bladders and in one space store fresh, gray and reclaimed though it would be more expensive.