Charities and for-profit businesses can often cooperate on promotional efforts that increase the sales of the business and generate valuable additional revenue for the charity. 

If, for example, the local hamburger chain franchise advertises that it will pay 50 cents to a local charity for children from each hamburger sold during the month of July, the company may increase sales while the charity will receive a nice contribution and a lot of good free publicity.  Consultants often call this cause-related marketing. The law has a different name for the relationship:  it is called commercial co-venturing.  And it may be subject to disclosure requirements.