From the New York Times on icky kitchens:

Chuck Gerba, a professor of environmental microbiology at
the University of Arizona who has studied bacteria in home
kitchens, said that he found that people who had the
cleanest-looking kitchens were often the dirtiest. Because
"clean" people wipe up so much, they often end up spreading
bacteria all over the place. The cleanest kitchens, he
said, were in the homes of bachelors, who never wiped up
and just put their dirty dishes in the sink.

My brother must be so psyched.

The truth is, as (a different scientist) pointed out, bacteria in the
home kitchen is simply not mysterious or weird enough. To
respond to it, you have to do something very banal: wash
your hands. And that's just not as compelling as taking a
dramatic stand and halting beef consumption in the face of
a brain-rotting disease.