There are countries in the world where ordinary white collar workers still have household staff, and perhaps you have heard some homesick immigrant moan, "Back home we had servants." Those are countries with large populations of destitute people who do not themselves have servants---unless, I suppose, they are very high-ranking servants like Nanny Hawkins in Brideshead Revisited.
That said, I don't think any woman taken by her own or her husband's work to such a country should ever feel guilty about hiring a local woman to cook, clean or chase after the children while she goes to the hairdresser or has a gin and tonic at the club. If suddenly you slip into the Wicked Colonial Past, you might as well take advantage of the perks. Such a perk is the Ayah.
Er, and when I say "take advantage", I mean hire at a decent wage. Here in the UK, hired help is less in danger of sliding into complete destitution, but naturally they should also be paid a decent wage. And no-one should ever be spoken to "like a servant", incidentally. Anyone who speaks to an employee as if she were dirt is obviously not far from the dirt herself, said some early incarnation of Miss Manners.
I have hired other women to do my housework only once in my life--when I had crippling tendinitis in both hands, thanks to stupid new innovations at my then workplace. Yes, I hired Molly Maid--and then COWERED in the laundromat down the street. My father's side of the family had "household staff" as late as the 1940s (which I know because a genealogy-mad friend looked up them up on the U.S. Census), but my mother's side never did, and as my mother retained a strong sense of "KNOW YOUR PLACE" back then, I felt deeply ashamed.
This was foolish, though. I was making a good salary, and I was temporarily crippled, so calling Molly Maid was indeed the right thing to do. Meanwhile, my brother and his wife, both busy working parents, hire a cleaner, and I doubt they think twice about it! In contemporary class-free Canada, hiring a cleaner is like hiring a piano tuner or a plumber.
That said, I don't think I will ever do it. My mother never did--she probably should have, hello! Five children, huge house, dermatitis! However, that was her choice, and whether or not to hand over your housework into the keeping of someone else is a very personal decision.