Why do Bolivian women wear bowler hats?

I saw a news report about Bolivia today and wondered why Bolivian women wear hats that look like men's Bowler Hats?

According to the Wikipedia Encyclopedia
The bowler hat has been worn by women in Peru and Bolivia since the 1920s when it was introduced to Bolivia by British railway workers. For many years a factory in Italy manufactured the hats for the Bolivian market, but they are now produced locally.

There is a controversy about this and it is not known for sure how and why the tradition arose - it might have been an overproduction dumped in South America. The hats were too small for the men? Someday it will be a Hollywood movie

The position of the hat can indicate a woman's marital status and aspirations. Another source says that it has something to do with fertility. Unlikely?

Go to http://www.travelblog.org/Photos/2490977.html
and see a picture of a typical Bolivian Woman wearing a bowler hat. They keep on wearing them - good show!