Commuter Clothes

I (attempt) to walk to work most days, so I try to create outfits that I like, and that I can walk a mile in (in the snow, uphill, both ways!). I keep a few blazers and my "work shoes" at work, which is great, so I don't have to lug those things with me on my daily grind. 
Needless to say, I usually look pretty casual on my way into the office, and I sometimes run into people in the elevator and am convinced they are judging me, and that I should assure them I will be dressing up. In reality, no one probably cares.

A typical example is below: I am wearing the same silk top and jeans in both, but walking to work I paired these items with a zip-up sweater and sneakers, whereas once I'm in the office, I slip on loafers and a blazer. 

A close-up of the office look:

                     Blazer | J. Crew  ||   Zip-Up | Alternative Apparel
                          Top | Theory (secondhand)
Jeans | DL191
                                              Shoes | Cole Haan  ||  Sneakers | Asics Onituska Tiger Mexico 66 ( last seen here)

I must admit that the commute sometimes keeps me from wearing my more delicate items, or anything I feel like will make me break a real sweat, and I save those for days when I know I won't be walking. 
What do you wear when you commute and how does it influence your sartorial choices?