I haven't gone through the other pages, so I'm probably restating someone else's ideas, but just because there are still panty hose companies, and displays at stores doesn't mean that women are wearing them in droves. There's a LOT of people in the U.S., and elsewhere. Sure some women do wear them, but mostly the over 50 crowd, and some younger women in more conservative parts of the country and in conservative professions.
My girlfriend works in a fairly conservative job and often wears them during three seasons, with skirts, usually for warmth. She's 29.
Me, I don't like them. I'll put a pair of "hose" on once in a blue moon, and usually wear bare legs or sometimes stockings/thigh highs for special outfits.