Actually, dirty bottles CAN BE sanitized...hell, they can be sterilized. Maybe not in a dishwasher though. You'd just have to pressure cook them long enough or autoclave them. Would they still have crap inside? Yes, but sanitized or even sterilized crap.
I didn't think about it quite that way. NiteOwlBrewing is correct: you CAN have sterilized crap at the bottom of a beer bottle. I don't WANT stuff like that in my beer. Don't think anyone else does, either. But at least it would be sanitized and sterilized.
glenn514