Put a expensive high hygiene rated sink in the kitchen and the cheap low rated hygiene sink in the bathrooms. From my experience Sims use the best sink in the house. The same goes for counters. Having expensive counters in the bathroom with cheaper counters in the kitchen allows my Sims to prepare food in the bathroom even if it's farther away. Also pay attention to what is on the wall or hanging from the ceiling and what clutter is nearby. Upgrade dishwashers if your Sim can.
I had cc cheap counters in the kitchen and more expensive counters in the upstairs bathroom. My Sims were going upstairs to prepare food and wash dishes when there were 4 open counters and a nice sink in the kitchen. I swapped out everything making the bathrooms less than the kitchen and now all is good.
If you take away all the sinks and have city living use the talking toilets. After the toilet knows your Sim more options open up in place of the question marks. Use and sanitize is one option. Even with a sink in the bathroom Sims will not need to wash their hands if you pick the use and sanitize option.
This is an annoying situation but no mod is needed. Just outsmart your Sims. The don't wash dishes where you angry poop is an awesome name for a mod!