I live in a resort town on the Gulf and all 5000 residents make a living off the Gulf in one way or another. If the tourists don't come to the beach, and we can't fish for food,The location is useless. The waitress at the Waffle House loses her job because of no business, so BP pays her also. It's not just the fisherman that will be reimbursed, the entire population will. I believe the 300,000 number is far too low. BP will work for us drilling for oil to make "OUR" payroll.
Except the fallacy in your analysis is that if BP replaces the income of the people directly effected, such as fishermen, and they are then able to spend as they always did, the waitress will not lose her income.