I love this club sandwich comparison. I am one who is reluctant to order this sandwich outside of the U.S.
I have found, when ordering a club sandwich in Europe, so many variables: The Clubs at the Gritti in VCE and Hassler in Rome are different than my local Club. Harry's Bar in VCE almost gets it right, but there is still too much stuff on the sandwich.
The sandwiches outside of the USA might include:
1. hard boiled egg
2. grilled chicken
3. Canadien bacon
4. fried egg
5. boiled ham
6. No avocado
7. No turkey
8. Cheese
OTOH, generally if one orders a burger, one gets a burger. Not a lot of variables.(except for price).