Ok I saw both folks.
My feeling :
There is much more difference between US - spain people (is it political correct to say that way?) and other US - aborigines,
as e.g. between US-aborigines and German-aborigines.
As for GB people I always told them , “Hi , are you from USA?”, nope ,
they all were from GB.
But back to your question.
What are the differents .
1. Germans don't play in Casino ( to clever or too boring , who knows).
GB and USA and China people like to spend some money just for fun
(too wealthy or too boring ?)
2. Germans would never stop you only to tell you how nice is the wather today,
or to ask what’s up.
But they would like to speak with you if there would be some "situation".
They would like to help you in any situation e.g. with baggage , but
you must tell them what do you need, especially if you are a young pretty lady.
3. Russian tourists would not speak with you a lot, but some Russian waitress (if any on board) would like to hear your boring small talk and old jokes.
Don't miss to say some compliment to them.
4. German tourist does not even know what is "tuxedo" and would not
made a overdressed family fotos, but you would see a lot of elegant
Europe people evening in restaurants .
You would never get a feeling that Germans are examining you, but be sure
the most thing they like to do is to drink some coffee, beer or wine and to gawk.
5. As you know for French tourists (especially if they came from Paris) you are normally not existing.
6. As I say GB tourists are nearly identical to USA tourists.
But much more crazy : I swear, I saw some GB fellow on Costa he come into
sauna in T-shirt, trousers and in sport shoues!
7. Never try to go on "German" ship into Sauna in slips or to close genitals in sauna -
that is "verboten" - and there is always 3-4 nice girs there.