I guess married men are pre-qualified in a sense - "Ted Bundy Syndrome" is off the table. They are seen as safe, experienced, and discreet...what more could a single girl ask for? LOL!
Married men, something the women can't readily have. Often women want what they cannot have, solely because they cannot have it. Married or 'taken' men often exude a degree of confidence, lacking in a hardup single.
Women often get caught up in the "Sex in the City" attitude....a show written by gay men. Some real-life women try to duplicate the lives of "Carrie & Samantha", but are left emotional and financial wrecks. Real-life men do not want to date them.