One possibility in understanding a difference between Oregon, WI and the places that you mention is weather.  Another possibility is demographics.  Many midwestern towns are becoming quite aged.  Thus, elderly don't want to walk far in bad weather.  I have first hand experience with this seeing my parents in a small midwestern town.  They will drive one place, and if the next place they want to go is a block away, they'll move the car.  Since parking is never a problem this is easy to do.  Please know that I'm not endorsing this.  I think this is largely cultural, everyone else does it so it's the norm.  I've seen how much people walk in NYC, including the older people who are in pretty good shape because of it and they don't question it because that is their culture.  I'm lucky that my town of 250,000 isn't too bad for biking.  I biked to our farmer's market downtown yesterday and carried the produce home in rear bike baskets, as usual.  I think part of the success of our's and other farmer's markets is that streets are blocked off so that for one time a week people can actually enjoy walking and lollygagging in an auto free area.  The atmosphere is so completely changed and festive from its normal auto invaded rat race.  I suspect farmer's markets held in or close to downtowns are much more fun to go to than on city peripheries.  One of my favorite sayings is "be careful what you wish for".  We wish to park close to where we're going but we've destroyed where we're going to.  I really sympathize with this coucil member because I know what he's dealing with.  No amount of public discourse will change these people's minds.  baby steps...
The elderly do sometimes have difficulty walking in bad weather, but really its hard for everyone when sidewalks aren't cleared of snow and ice, which occurs in places where they don't give a damn about people, only cars.  Around here, they used to actually plow the snow from the street so it piled up on the sidewalk which made getting to work quite a challenge even for able-bodied me.  They now don't do that on main pedestrian routes (at least).

One thing, though when people bring up elderly - you need to look at when people get old, can they and should they be driving?  My parents are both in their 80's and can't drive any more due to a very common low-vision condition (macular degeneration).  I think there are many others that probably shouldn't be driving that are because to stop would mean a total loss of freedom.  If they do stop driving and don't live where they can walk or have access to some type of transit, their options are really limited.

Arlington provides a paratransit service for people who need and qualify for it (typically elderly/disabled)

http://www.commuterpage.com/paratran.htm

Yes, you bring up another big problem.  Elderly cause many of the traffic fatalities around here.  But try to convince them to give up their cars... A neighbor was telling me how her 92 year old mother who lives in an eastern state can't see very well to grocery shop, however she drives to the grocery store!
I prefer walking above all else.
I cycle if it's too far to walk and drive if I can't cycle it.
Macular degeneration for the most part is likely diet related.  A diet high in cholesterol (animal products) will not only steer you towards heart attacks and strokes but also take your sight from you.

http://www.nealhendrickson.com/mcdougall/031200pumacular.htm

As for the elderly driving - I've seen it.  They know that they're having problems; the kids hope that the license doesn't get renewed; the doctor punts and doesn't block the renewal.  In a year or two they eventually come to their senses and the ones I've seen self-restrict themselves to daytime only ....  It's not right - but it's very hard for us to give up something we've taken for granted for decades.

I complained about the lack of free parking at my current employer as I had a decade of free parking under my belt.  I was floored when parking went upto $3 per day - it's cheaper to take the bus and still the parking lots are jammed at this university.

Would you mind sharing your age praetzel?  I appreciate your lifestyle and health.  You are exactly right about diet and daily activity!  Bless!