The feet on the table did occur to me as one which I could have the wrong way around and while only "slightly wired to predict that feet are smelly or covered in dirt" may be true (seems unintuitive to me though), I think the perceived discrepancy is cultural as much as anything. I've noticed the ickyness of putting feet on tables is almost universally invisible to Americans, while in Japan it would seem completely unacceptable along with a whole host of other related customs, for example, the taking off of shoes and the special slippers to wear when you use the bathroom. Japanese ask me extensively about UK customs regarding shoes and feet, it's evidently considered a hygiene issue, much like their showering before bathing. In the UK the foot thing is probably a bit of both, varying from person to person, family to family. I was brought up such that I wouldn't ever consider putting my feet up on a table, even when completely alone in my own house. Our trains have signs telling you not to rest your feet on seats, I wonder if US trains do. What you say actually now reduces the offense that I would take if an American put their feet up in front of me. I would think "well for them this isn't considered gross, just a sign of relaxation that at worst is dominance behaviour" and I'd attempt to force myself not to be disgusted by it.
One other thing might be that outhouses were an American innovation[1], imported to other parts of the world later; and thus, of all rural-living subcultures (which are the usual source for a culture's hygenic mores/superstitions, being the most affected by them), rural Americans have had the longest to adapt to not worrying about getting shite on their feet. :)
The feet on the table did occur to me as one which I could have the wrong way around and while only "slightly wired to predict that feet are smelly or covered in dirt" may be true (seems unintuitive to me though), I think the perceived discrepancy is cultural as much as anything. I've noticed the ickyness of putting feet on tables is almost universally invisible to Americans, while in Japan it would seem completely unacceptable along with a whole host of other related customs, for example, the taking off of shoes and the special slippers to wear when you use the bathroom. Japanese ask me extensively about UK customs regarding shoes and feet, it's evidently considered a hygiene issue, much like their showering before bathing. In the UK the foot thing is probably a bit of both, varying from person to person, family to family. I was brought up such that I wouldn't ever consider putting my feet up on a table, even when completely alone in my own house. Our trains have signs telling you not to rest your feet on seats, I wonder if US trains do. What you say actually now reduces the offense that I would take if an American put their feet up in front of me. I would think "well for them this isn't considered gross, just a sign of relaxation that at worst is dominance behaviour" and I'd attempt to force myself not to be disgusted by it.