Why good manners is a deal breaker
Men open the door for women, walk on the outside when walking a woman down the street, sit down at the table and eat only when the host and every other person has been seated, and mostly, without a pocket full of cash, they are the first to invite someone over for dinner or to try their fresh tomatoes that they planted early on in the season. It's these good country manners and hospitality that reminds us that it isn't too hard to be kind and display good manners.
There really is a lot to be learnt from country folk.
While I don't expect all people to be at the level of a "Swiss Finishing School", good manners is a sign that people are considerate of the those around, respect that they are in company and whether they like the person or not, know that good manners is more about them then the people who they surround themsleves with.
My basics: I would be mortified if my brother's didn't open the door for their wives or friends, or didn't walk a lady to a taxi. It is these simple things that are confusing men and women today as to what is right and what is wrong.
How can you tell if you should or shouldn't open the door? The right answer is you should. Full stop. No question. If the person is rude enough to ask you not to, then step away, and politely apologize, to ensure that you don't cause a drama.
Here is a great article on 13 Good and Bad Manners from around the world. Check it out and let me know what you think http://people.howstuffworks.com/13-examples-of-good-and-bad-manners-around-the-world.htm