Originally Posted by jackal

Given that most Americans don't know this rule (I certainly didn't growing up, and I don't by habit follow it now), I highly doubt it.

And FWIW, I've never paid attention to when the server clears the plates off of the table, and I certainly don't find it rude when they remove a dishes from the table. So it's not that Americans put up with this kind of "horrific" behavior--it's that it never crosses our minds that it should be any other way.

Actually, I take that back--just last week I was out to lunch with my aunt and cousin, both of whom have worked as servers. We had a particularly new waiter, and when my aunt and cousin were finished eating but I was still working on my meal, they were left with their plates in front of them. The server actually came by twice to check on us but left the dirty dishes on the table. Both my aunt and cousin remarked that he should have taken their dishes away. So I suppose I have paid attention to this, but it was in exactly the opposite way you describe!

It's kind of like fork-and-knife etiquette: keeping your left hand on your lap is taboo in Europe, but in America, there's no such cultural prohibition, so it never even crosses our minds that it could be rude. (In fact, it looks slightly rude--possibly even uncivilized--to us for someone to keep both hands on the table unless one is actively using the knife to cut the food.)