Quite possibly some numpty marketing or PR person probably thinking they are being clever. But this kind of tactic just spoils the reputation of any website that is otherwise quite popular.
If you don't know, the one quoted is a pay-for-entry competition. It has been going for years and has had thousands of entrants I would imagine by now.
Real success stories I think are rare. But that's just the nature of songwriting generally I guess. Point being, there are more commercially successful songwriters who haven't won that contest than those that have.
Of course, it is only because I have won song of the month on here twice in the last year that I am the millionaire successful songwriter that I am. Save your money and stay on here, says I!