This 'initiative' (I personally would call it an experiment) is funded by BBH New York, an advertising agency. They are trying to "modernize the street newspapers model employed to support homeless populations".
The idea is to have the homeless provide a service that's always in demand in today's tech savvy world. So instead of begging for change, the ones with these devices can charge (a recommended) $2 / 15 min, although the customers are allowed to pay as much or as little as they want. For those that do not have cash on hand, the website facilitates payment through paypal and all proceeds will go to the respective person providing the 4g hotspot.
I really like this sort of experiment. We are always constantly checking our tweets, messages, emails as often as we can and this provides a way for those without 3g or 4g a service they want, and can help the homeless at the same time.
There are thus far, 13 participants that have been enlisted in this experiment (as of this post). The experiment is taking place in Austin near the SXSW convention center.