They seek to increase personal engagement and positive outcomes by rewarding contributors in an open way.
The risk of bankruptcy of such open-movement businesses is reduced because the fruits of their work remain in the commons and therefore remain as a permanent base for recovering the open business, even in their most critical situations.
Another example might be Canonical Ltd. Open businesses can be more attractive to donors, especially if the name of the donors in social networks (as real names, Twitter-, Facebook- or other branded Online Ids) are made public too.
So in this case even the donors participate in the charity as business and beyond by increasing their positive community karma (earning "whuffies") and building their reputation.
The risk of bankruptcy of such transaction-oriented businesses is reduced due to the fact, that The degree of freedom to participate may vary: