Well, there are 26 photographers already listed, so if they all paid £30, he's on his way to a nice new camera already.
I dont think its scam as such just someone trying to make a bit of money, but not very well thought through. The payment system is just a paypal cart, so essentially people are buying direct from you, not from the site, as the small print mentions the paypal fee's you'll have to pay for each sale.
I think I'd rather stick with the world famous Alamy for free and not get any sales then spend £30 a year with a no name site and not get any sales.