A consideration: can someone who earns less than $80 for a day's work afford to live within driving distance of your house? In India, definitely; in a US metropolitan center, definitely not. (This reduces the problem to the much-better-studied, "people really don't like relocating thousands of miles away for a job, even if their life currently sucks.")
It's $80 for 2 hours. You can survive within commuting distance of Manhattan on $15/hour. You might need to commute from NJ and suffer the indignity of having roommates and black neighbors, but it's quite doable.
I lived within commuting distance of Manhattan during grad school on a stipend roughly equivalent to a $10/hour x 40 hours/week. Prices have gone up a bit since then, but only enough to push me 15-20 minutes further out.
You realize that most of the time, when you're hiring someone to clean houses, that most of the money is going to an agency that has overhead, right? Who is answering the calls to set up the appointments? Who is paying for the cleaning materials?
That cleaner is likely making close to 15-20 an hour.
Okay, admittedly, earning $40/hr at any job is well above "marginally-employed", so we're both being a bit silly here. It's more those who expect people earning minimum wage to somehow survive in a city that I was aiming for.
Just because you're billing $40/hr doesn't mean you're well above marginally employed.
We're talking about a 2 hour gig here. There's likely to be at least 2 unbillable hours involved in a 2 hour gig gig, so your rate is already cut in half to $20/hr.
Once you start taking into account all of the unbillable hours (including time spent finding gigs) and all of the downtime between gigs, a $40/hr rate could very well mean you are below the poverty line.
A consideration: can someone who earns less than $80 for a day's work afford to live within driving distance of your house? In India, definitely; in a US metropolitan center, definitely not. (This reduces the problem to the much-better-studied, "people really don't like relocating thousands of miles away for a job, even if their life currently sucks.")