White House Correspondents Dinner Question

I know that the White House Correspondent's Dinner is all good fun and I look forward to watching it as much as the next guy but I have a question - who pays for this dinner? Just the cost of the secret service detail alone is bound to be prohibitive and if this is something which the taxpayers foot the whole bill for then I think it is time to end the tradition.

I tried to find out who is responsible for paying for this event but was unsuccessful. I have to assume that the White House Correspondents Association foots the bill (not including the secret service costs).

One has to wonder about the utility of the event. It is supposed to be for White House correspondents but looking into the crowd at the dinner you see almost as many NFL quarterbacks (Eli Manning and Ben Roethlisberger and former Giant Phil Simms) and Hollywood stars like George Clooney as actual journalists. With layoffs epidemic and stock prices dropping through the floor at newspapers such as the New York Times - I wonder what message is being sent by journalists in tuxedos when the average journalist makes as much as the Dominoes delivery guy?

If the event is funded by selling tickets or "tables" and most of the people attending are no longer journalists - then how appropriate is it for the President of the United States to be the "headliner" at such an event?