I feel sorry for those people because I have an inkling of what they have to go through. Most of those positions are done through the PIRGs (Public Interest Research Group and their affiliates, the group cofounded by Ralph Nader back in the 70s). I don't know what the PIRGs were like back in the day, but at this point, they are basically the Wal-Mart of non-profit organizations. My girlfriend had a PIRG job after college, where they forced her to work 80-100 hours a week on salary (which meant she was making well below minimum wage since there was no overtime pay). They forced her to canvas even though it wasn't in her original job description, and basically what they'd do is drop you in a neighborhood and abandon you for 9 hours. The weather was irrelevant; you had to do it rain or shine. If you didn't make quota, you were reprimanded.
After a couple months of this she was fed up. She got together with a coworker who was also fed up, and they attempted to unionize the Massachusetts branch of the PIRGs (MASSPIRG). This was shortly after the Los Angeles PIRGs tried to unionize, and the PIRGs responded by completely shutting down the LA branch and firing everyone. Well, a similar thing happened in Mass; my girlfriend and her coworker were fired, and a bunch of other people quit, leaving several of the college campuses in the area without any PIRG representatives (my girlfriend was successful in a bid to get the students to vote to reject the PIRGs charter and get them kicked off campus).
The PIRGs are a worthless organization. They abuse their employees, they violate minimum wage and overtime laws, and they actively break unions. They are the epitome of everything Ralph Nader was against in the 70s; how that happened is anyone's guess.
But the point is that these poor people on the street doing surveys are getting fucked. They are trying to scrape together a living in one of the shittiest jobs you can imagine. Give them a break; it's not their fault that they're out there (I just used all three there homonyms; I rule).