Where have the nurses hats gone?

Where has style gone in Hospitals? Perhaps style has no place in Hospital? The above is a picture I recently acquired at the Antique Market here in Toronto. Most of the nurses are actually closing their eyes. It was Christmas but I doubt that they were drunk. The flash was too strong perhaps? I did a lot of searching on the internet to see if I could identify the style of the hats on the Internet. This is a big job since each School of Nursing had its own style. I was not successful in the identification. Some of the styles were clearly based on the Catholic Nun's Habit others a style of their own. I found it difficult to guess the period here. One of the ladies in the back row is in civilian clothes that could be from the twenties, it's pure guesswork. Can anyone help me?
Nurses uniforms in North American have evolved to "scrubs" similar to those worn by doctors. This appears to be a revolution that took place in the 1970s/1980s. In other countries nurses have kept to tradition. Why the change? Here are some reasons given:

• The hats were not unisex and the profession wanted to attract men - they can do heavy lifting that is a real problem for nurses. A lot of injuries from the strain of lifting.
• The hats were not professional and marginalize women.
• The hats were not practical and could harbour germs (?)

It seems a pity that a tradition died. Can we at least bring them back for special occasions? If you want to read some background on nursing history go to the Canadian Museum of Civilization and read the discussion there.