As a recreational boat owner, you need to know the difference between a passenger and a passenger for hire. Otherwise you may find yourself at odds with the authorities, a circumstance that could lead to fines and/or inadequate insurance coverage.
The Federal Safe Boating Act of 1971 advises that a passenger is a guest onboard a vessel that is being used exclusively for recreational purposes (non-commercial) who does not contribute any consideration, either directly or indirectly, for his or her passage. If there is consideration paid, the boat is a commercial venture and the captain and any crew must have the U.S. Coast Guard license designated for that purpose. This sounds simple enough, but there are shades of gray that can cause the unwary captain some difficulty.
For instance, if you take out a group of people for an afternoon on the water, charging each a certain amount of money for the privilege, it is an obvious case of passengers for hire. But what if your passengers decide to chip in for gas? Are they contributing consideration? What about if they bring food or beer?
For legal purposes, "consideration" includes economic benefits, inducements, rights or profits accruing to the owner and/or the captain. In 1999 Congress refined that definition to permit voluntary sharing of expenses on a voyage via contributions of money, fuel, food, drinks or supplies.
The key word, here, is "voluntary." If a passenger offers to help with expenses in some way, that is a voluntary act. If, on the other hand the owner/captain initiates the topic with a requirement for a contribution or even a suggestion that a contribution would be appreciated, the donation would no longer be considered a voluntary sharing of expenses, and the passenger(s) would then become passenger(s) for hire.
Keep on the right side of the law. If your passengers volunteer to share expenses, express your appreciation, but let them know they are under no obligation nor is there any expectation that they do so.