Equally strange, I think, is a phenomenon in the shower at the gym / pool that I go to.
There seems to be quite a few guys who shower with their bathing suits on. Now this, in itself, is not that odd. However, alot of them wash with soap, and vigorously scrub their nutsacks, inside their suits. I find it strangely unerving to enter the shower, and to see a guy who has both hands thrust inside his bathing suit, (presumably) scouring their balls.