Mturk is great because it is a service supported buy a great company. You know that if you work, you will receive your money. It is hard to trust in a company that nobody knows where you could eventually works for free
I don't agree with anything you've said. It's almost the same as slave labor, you can't ever think to support yourself doing work like that.
Companies are just leeching of off low-skilled labor and I know that some people really do try to make a living out of it.
Sure, they will pay you for the work you've done, but the rates they're offering are just not worth it.
Thats the thing with online work, you are competing with people that only make a few dollars per day in their country. $2/ hour is nothing in the United States but in certain countries that can be a decent amount. Globalization has really brought down wages across the board but especially in jobs that are not location dependant.