LOL - I agree. First, spending a flat 25% of one's income gambling is a concept I think many men and women would find imperfect

Secondly, few people can regularly take time off their jobs to physically attend a race track multiple times a week.
But the above is not the only scenario that defines a gambler. Busy professionals may not gamble frequently, but they certainly have the income to gamble significant amounts of money when they chose to. And women are a large part of that group today.
I know several women who spend a good amount of money ($1000 or more) monthly, and quite a few who spend a little here and there. As I said, ADW's make it easy.
Keeneland is a boutique meet, certainly, but look at the numbers of women walking up to the windows there. Churchill, Turfway ...
Women don't want to go to an OTB. I can't stand Keeneland in winter - drunk, swearing, loud guys rule the roost many days on the general open floors. But TV and an ADW make racing - and gambling - easily accessible.
Women also don't generally feel the need to publically compare the size of their winnings thus I think fly under the radar more (look at this board).
I know some like to picture themselves as hardened racetracker originals, big spenders and tough gamblers, etc - feel free to embrace that, but it's far from the only paradigm. Cigar-smoking college guys throwing away a couple hundred a day may rule the apron at Keeneland in spring, but upstairs - and at home - there are plenty of people quietly pursuing a more businesslike model to gambling, and that takes significant disposable income, and women are right there. Don't discount a huge potential audience of intelligent, risk-enjoying, high income people just because they don't have peni.