Why are the marriage rates down?

Instapundit links to an article in Studyfinds.com asking why marriage rates are down. The study suggests it may be because there

aren’t as many economically-attractive men for unmarried women to meet as there used to be.

Glenn Reynolds, however, notes that

Well, with the obesity epidemic, there’s also a shortage of ‘physically-attractive’ women, but I guess it would be sexist to mention that.

In the comments section, Larry writes,

A department store opened in New York City that sold men and a woman decides to visit it in search of a husband.
At the store’s entrance, there’s a sign outlining the department store policy.
The first rule states that you can only enter the store once.
There are six floors and on each floor you can choose a husband or elect to move on to the next floor.
You cannot visit a floor more than once other than to leave the building.
The woman visits the first floor.
The sign reads:
· Men with jobs.
She moves on to the second floor:
· Men with jobs that adore children.
She moves on to the third floor where the sign reads:
· Wealthy men that adore children and are very handsome.
She thinks to herself, “that’s a very good deal” yet moves on to the fourth floor:
· Wealthy men that adore children, are very handsome and help with the household chores.
She decides to move on as things are constantly improving:
· Wealthy men that adore children, are very handsome, help with the household chores and are very romantic.
The woman is about to make her purchase but can’t resist moving on to the sixth floor.
There the sign reads:
· You are visitor number 31,456,012 on this floor.
· There are no men here.
· This floor exists as proof that it is impossible to please women.

& MEN…

Opposite this department store, another department store opened that sold women. The sign on the first floor reads:
· Women that love sex.
On the second floor the sign reads:
· Women that love sex and are wealthy.
On the third floor the sign reads:
· Women that love sex, are wealthy and have large breasts.

Not a single man has visited the fourth floor.