oh, very good.  Like that.

and the pun was actually rather good as puns go.

Having given it no thought whatsoever until I posed the question, here's what I came up with as suggestions at 3 o'clock this morning when I couldn't sleep:

- impolite to turn up less than X hours before posted time of ship departure

   (where X is some combination of starport type and law level I've not worked out yet). 

    (But probably not less than an hour even on an E-class low law level world)

- impolite to make demands on the ship's steward an hour before departure and during transition to orbit except in an emergency

   (the steward may well have flight duties)

In shared Middle Passage accommodation:

- polite to stow carry-on gear at all times

- impolite to bring another passenger back to bunk overnight [1]

- polite to discuss with other occupants any changes in grav setting of a stateroom, or major environmental control changes

- impolite to fail to show up for an invite to a meal at the Captain's table

- impolite to monopolize steward, especially on a small ship where there may only be one

- impolite to monopolize shared passenger space (such as lounges) with noisy/smelly/space taking hobbies/music etc without prior arrangement

- impolite to ask about a ship's cargo beyond what is posted in public manifests (unless crew bring up the subject)

- polite to remain in designated passenger spaces at all times unless at express invitation of crew (on some ships this may be legally enforced or physically prevented by locks rather than mere 'etiquette')

- impolite to monopolize exercise equipment, where available

- polite for furred sophonts to notify steward if moult occurs during passage (cheapskate captains may charge extra for additional steward, or in serious cases engineer, filter cleaning/replacement)

- impolite for Mid passengers to complain about food standards.  (Whereas it's almost de rigueur for High passengers)

<checks to make sure he's trimmed previous post and that the subject line is still relevant>

tc

[1] Remarkably, this actually happened to me.  As a young single man I travelled to Sweden on an overnight ferry and shared the cheapest possible accommodation consisting of a four berth cabin down in the bowels of the ship with a Swede in the bunk above me.  We'd chatted a bit through the evening's entertainment on board but then parted company as the guy went on to the (casino?) and I went to bed.  Some time in the small hours I awoke to find a naked Swedish girl climbing into the bunk above.  To be fair to them, aside from these 2 or 3 seconds, they disturbed me not at all.  Back in the womb like warmth and engine sounds of a ship after a few months back home following two years living aboard a ship, I slept like a baby.  Also to be fair, I didn't see it as impolite.  Just as an initial surprise - and perhaps a subsequent jealousy!