String theorists are notoriously protective of their mathematical purity. The meme captures that perfect moment when brilliant physicists who spend their days contemplating 11-dimensional vibrating strings and parallel universes suddenly transform into germaphobes over some tap water on fruit.
It's the ultimate physicist paradox - comfortable with the idea that reality might be a holographic projection, but utterly horrified by local water quality. The Bangalore water situation just created the world's most educated group of hypochondriacs.