The big downside with washed eggs is the shelf life from what I understand, I happily keep unwashed eggs at room temp for ~a month, whereas I from what I understand eggs in the USA would need to be refrigerated and still wouldn't keep as long.
I get 3 weeks with my (refrigerated, American) eggs no problem. I think our American fridges probably tend to be larger than European ones, so space in it isn't at a premium.
