The real issue is that the drain trap is much smaller for a shower than that in a toilet even if the pipes are the same diameter.
The waffle grid is for the exact purpose of stopping things that are too large for the drain trap, so theoretically it should be fine. If it passes the grid, it can pass the trap.
However, the drain trap doesn’t clean out entirely every time. If you stomp shit into the drain, then the trap will contain shit until it is cleaned out. It will also smell like shit, which defeats the purpose of having the trap in the first place.
Drain traps are disgusting enough without the addition of shit. Even in best case, it will accumulate hair mixed with shampoo and conditioner. I doubt that mixing it with shit will generate any kind of water savings, because it will require a thorough cleaning more often. Also, the main pipes actually needs a lot of water to drain. If by saving on water you eventually have to call a plumber to blast out the fat-bergs it will require a whole lot of more water.
The real issue is that the drain trap is much smaller for a shower than that in a toilet even if the pipes are the same diameter.
The waffle grid is for the exact purpose of stopping things that are too large for the drain trap, so theoretically it should be fine. If it passes the grid, it can pass the trap. However, the drain trap doesn’t clean out entirely every time. If you stomp shit into the drain, then the trap will contain shit until it is cleaned out. It will also smell like shit, which defeats the purpose of having the trap in the first place.
Drain traps are disgusting enough without the addition of shit. Even in best case, it will accumulate hair mixed with shampoo and conditioner. I doubt that mixing it with shit will generate any kind of water savings, because it will require a thorough cleaning more often. Also, the main pipes actually needs a lot of water to drain. If by saving on water you eventually have to call a plumber to blast out the fat-bergs it will require a whole lot of more water.