it’s not illegal to ask if they are legally allowed to work in the US.
I’ll bet the person asking why you can’t just hire legal doesn’t regularly hire cleaners. Or they would know how much harder it is.
People pay above minimum wage. Hiring illegal immigrants doesn’t mean you pay below minimum wage, that is not the point. The point is to find someone willing to come regularly for a price (above minimum wage) that won’t bankrupt you.
Lots of people need cleaning help, I’ll bet the ones saying those who do are lazy aren’t actually working mothers with a bunch of kids. Probably more likely to be bored guys trolling who don’t know what it is to be a working mother with kids.