Like most here, I don't wash unless there is obvious poop, and then it's just a quick rinse under the garden hose.
That being said, I don't delude myself into thinking that the poopless eggs are any less germ laden than the poopy ones.
Seriously, when you reach your hand into that nest, or pet your chickens, or fill their feeders/waterers, you are inoculating yourself with salmonella germs, not to mention what you are tracking back into the house on the soles of your shoes. Didn't think of that now did you?
All it took were a few microbiology classes to destroy the illusion that things are clean if they look clean.
Life with chickens (or other livestock) and all their poo makes me curious to ask this further question . . . how many here find that you seem to have tough immune systems and are less prone to colds and flus than your non farming friends?
IMHO I think being exposed to continual low levels of germs is good for the immune system. My kids were always super healthy when little, and as adults they still seem to have rugged immune systems. I've worked in office settings where viruses ran through the building and folks were dropping like flies, yet I dodge the germs every time. I chalk it up to daily exposure to barnyard poo.
For those who give their flock eggs: you might want to give that a second thought. It is said that once they get a taste for egg they are far more likely to start beaking eggs in the nests. Perhaps it's a wives' tale, but I've always avoided giving them eggs just in case.