crossing cultures

Slovak people will not sit down next to someone they dont know on a crowded bus, but in a crowded restaurant, they dont have a problem sitting down at a partially full table!
Yesterday we went to a different restaurant for lunch. There were 8 of us to find a table at noon. As it turns out, this was not going to happen. So we split and sat at two part full tables. This situation was a stretch for me. I commented to Ander about this, and he told me that I didnt have to touch them, share my food or even talk to them, and the other option was leaving. He was surprised because in NYC strangers sit down right next to each other on the subway.
So why do we define something like sharing a lunch table in a restaurant as an intimate thing, and not sitting next to a total stranger on the bus?

CULTURE that's why. Culture pops up in the strangest places. Phrases you use. ever think about how many different ways we use the word "blow"?
the wind blows
we blow out candles
Bombs blow up
enlarging a photo is blowing it up
inflating a beach ball is also blowing it up
blow is a drug

Think about the word "Hang".....

how about why you could say you were "on the bus" without someone thinking you were standing on the roof, but it doesnt work that way with a car?

Being faced with my weird culture and language and the fact that i cant really explain it, i am trying harder to ask "is there a reason for that?" rahter than "Why do you do that?" becasue chances are the "why" is jsut because that's how it is!