unexpected expectations

i just had a reasonably strange dinner. no, not quite strange. just, i had the feeling that i didn't know what was going on.
let me sum up.
i had an american couple over for dinner (Mr is a visiting professor at Esigelec and his wife came along to France- very nice bush hating people; my kind of americans) .

Dinner, where people sit down and eat a meal. however where i live dinner is yes, for the purpose of filling your stomachs. which we did admirably. But, the social and cultural behaviors that go along with dinner (when you aren't eating alone) are really quite, well, they are to be respected. Not even in "an afraid to be committing a faux-pas" way, that's the funny thing; nothing they did was truly wrong, but several things caught my attention.

thing 1. before dinner we have "apero". where we have a coctail and eat snacky-type things. this in order to wake up the appetite and the discussion. Well, they didn't come to the table to eat my snacky type things. and they didn't have a coctail. and they stayed in the 'living room' part of my salon and didn't spontaneously come to the table.

thing 2. they didn't wipe their plates clean after the main course for the cheese course that comes after.
now, not wiping one's plate can seem a triffle insignificant in the grand scheme of things. However there is a definite purpose for this. When you wipe your plate clean (with of course un morceau de baguette) this means no sauce or remnants of the last course will contaminate the cheese you put on your plate. this, mes enfants, is important.
a whole new course requires a clean plate. De coup, when they took their cheese they didn't have plates.

thing 3. they didn't stay; they didn't stay for dessert. who leaves before dessert? and they didn't stay for conversation. that's largely the point of dinner, is the conversation.
dinner on a friday night is meant to last way too long. i was just at the beginning of my buzz when they had to leave. Didn't anyone tell them that's when the conversation starts getting good? Alas, being visitors they had to succumb to the whims of public transportation and it's limited availablity.

they did bring wine though. that's always a welcome gesture.

Now the mini-moral of the story is that i have become just frenchified enough for these trivial, teeny things to irk me. but in the end, how could they know that the bread is not only for eating but for preparation for the cheese?