Clean Wash Basins

At work in the cafeteria, we have wash basins all lined up for washing hands etc. What bugs me a lot is the state in which people leave it once they are done with. Morsels of food stuck on the basin walls. Yuck. I have no interest in what you ate.
It really doesn't take time to clean by just throwing a bit of water on the walls.
Many people stare at me incredulously while I clean the basins before using them and also after using them.
But I guess that's me being me.