Where there's a will there's a way. I've known women from all states of life who made multiple retreats. Women with children can get a babysitter*; women with full-time jobs can take a week vacation for it.
*I know this is not always possible, depending on the circuмstances, but many families have made it happen.
I agree. It's not so possible that you can blame those who can't swing it. It's not easy, and for some it just isn't possible. But many have made it happen over the years. They just need to arrange for babysitting. And speaking of being impossible for some, this is more likely if you have a lot of young children. As your kids get older, it's easier to find people willing to babysit for children who can basically watch themselves and/or help watch their younger siblings at the relative's house. All they are concerned about is how much work it's going to be for them.
That's why you want to go on a retreat before you get married. Highly recommended.
And I know that women are more likely to want to go, again and again. The Seminary in Winona used to restrict how often women could go, to make room for first-time retreatants. The women's retreats were always full. Of course, the Seminary could only host retreats part-time during the yearly summer vacation.