As someone who lives in a rural area, I can tell you that UPS charges an additional fee for delivering to a rural address. Their definition is "A Delivery Area Surcharge applies to Air and Ground packages delivered to higher cost-to-serve ZIP Codes. The surcharge is $2.20 per package for residential addresses and $1.40 for commercial addresses." Here's the text page that lists all the zips that fall into this category. http://www.ups.com/media/en/xarea.csv
I believe FedEx charges a fee as well.
Since it is based on zip code, I would think that UPS should be calculating their own costs right, but you just never know... :rolleyes:
Hope this helps...