It seems like any time there is a legitimate need fulfilled by the Internet, before long, unscrupulous people will try to capitalize on it and take advantage of innocent people. Online surveys are one of those legitimate undertakings that now has its share of scam operators.
Marketing research firms do exist and they do pay people to fill out surveys. But promises of hundreds of extra dollars per week, or getting to quit your 9 to 5 job are often scams. The way to make money taking online surveys is to sign up with 15 or 20 marketing research firms, and take the time to fill out every survey they send your way. This may be one per month, or even less often. That's why it's important to sign up with so many.
Many of the scam operations know that there are people eager to leave the "rat race" and start working for themselves. In their zeal to become their own boss, they may jump at opportunities that will take their money and not give much in return, if anything. You're better off searching for marketing research firms through the help of legitimate online forums where real people discuss their real experiences, both positive and negative.
Once you find legitimate marketing research firms, you have to sign up with several of them to have any chance of steady work. Many firms only send out surveys once a month or so. That's why you need to sign up to so many. And you do have to take the time necessary to actually complete the surveys and submit them. If you do enough of them, you'll start getting some income. Whether it adds up to enough for you to live on will depend on your standard of living and your willingness to put in long hours.