Wall Street and Silicon Valley may be excited about the emergence of the so-called sharing economy, but freelance workers driving for Uber are getting "screwed over," said Steven Hill, author of the new book Raw Deal: How the "Uber Economy" and Runaway Capitalism Are Screwing American Workers.

"The drivers who are driving it the most and trying to make a full time living at it, they are the least happy," said Hill. "Those who are doing it part time for a little bit of extra money, they don't mind doing it until they have experienced a couple of Uber's wage cuts, which come on a regular basis."

Hill is a senior fellow with the nonpartisan New America Foundation. He is also the author of five books including Europe's Promise: Why the European Way is the Best Hope in an Insecure Age.

Increasing numbers of U.S. workers, he points out, are suddenly finding themselves on shaky ground, turned into freelancers, temps and contractors, with low wages and no job security or safety net of support. Hill said that the job reports Wall Street traders anxiously await each month are not capturing the true picture of employment in America.

"What they are missing is that the number of 1099 forms, which is the form contractors file with the IRS -- those are climbing very fast," said Hill. "The number of people filing Schedule C, which is the self-employment form, those are climbing very fast. So I don't think we are capturing accurately what's going on in this gig economy."

Hill said the emergence of the gig economy has enabled employers to dump many of their full time and salaried employees, replacing them with cheaper freelancers and independent contractors who do not receive benefits.

"If it's working for you and you have that flexibility, then that's great," said Hill. "But the idea that these jobs are going to replace the jobs we lost as a result of the economic crash in 2008 and 2009, it's just not real world."