News Flash: People are different. Really!

Why does it continually surprise me that other people are sometimes different than I am? I know it to be so, but when I encounter an example, it surprises me. Some examples:

• I was eating lunch at work yesterday, and I should add that perhaps one or two other people may go by when I'm there, but this is not a lunchroom of the everyone-goes-there variety. And a woman came along and said, "May I join you for lunch?" It turns out she's new, and she and I had a very pleasant conversation before I had to go run my errands (post office and bank, tra la). And I'm not bothered that she joined me, but it surprised me. I would never interrupt someone obviously in the middle of reading the paper (as I was) or a book, and especially not if I was new. Good for her, really, but I know I wouldn't have done it.
  
• If I am faced with a box of assorted chocolates, the caramels are always my first choice. Thus, if I find caramels left in a half-eaten box of chocolates, it startles me. I recently found a caramel as one of the last two in a box, and whoa, weird.
  
• My drive to work takes me past a reservation area*, which at this time of year is not even sunny at 8AM, and yet there are always cars parked at the areas along it, which means (follow my logic here) that there are people out in the woods. Up early, in the cold, and this morning in the fresh dusting of snow**. I can only assume that ALL of them cannot have been forced there at gunpoint, yet that's the only way you'd find me there.

*The kind that preserves nature, not Native Americans or (if you, like me, have been reading Patricia Briggs' Mercy Thompson books) the fae.
**Yes, snow! I had to clear off my car! It hasn't snowed here since that freak October snowstorm. Shh, don't jinx it: knock on wood!

Do you have examples from your own life? Or am I different even in being surprised by differences?