Can urban farms feed people affordably and provide jobs - Can they be sustainable?

Are urban farms going to do enough - that is, feed people affordably?  It can be a struggle. 
Video Produced by Daniel Guillemette, Michelle Ha, and Grant Burns.in the Thunderbird (UBC news April 2010)

"Urban farms struggle to provide low-cost food

in East Vancouver is part of a larger project to provide locally grown food in . However, it is finding it hard to grow produce at a cost that is affordable to the people in the area.
The farm is only able to offer only six jobs to Downtown Eastside residents, and none of its first harvest will be made available to the neighbourhood. Instead, it is planning to sell its crop to high-end restaurants in order to pay the bills."

It isn't just urban farms, either.  Some small farms are intensively growing food which ends up going to high end restaurants and resorts, feeding tourists who crave experiencing all that their tourist destination has to offer - and leaving the locals choosing between fresh, high-end and high-priced local fare from a farm stand or farmers market, and affordable, trucked in yet good quality produce from the grocery store.