I grew up in central Pennsylvania farm country. This is a conservative area that has voted republican in every presidential election since Lincoln. The area is also rich in both Amish and Mennonite families. When a whole area is so packed with conservative ideas and individual it has a strong effect on what is "common sense". Common sense is not generally universal it is culturally based.

The best example I can think of is that 85% of the kids in my High School had the same haircut and rarely left the area. Suddenly mTV arrived on cable and the kids and hairstyles went wild. I know of parents calling the cable company to get mTV removed from the home(unsuccessfully).

It is simply a cultural standard.