There is a report in the SMH about how Cricket Australia has cancelled a heap of Ashes Tickets sold on eBay after the purchases sold them for more than their face value. They did it since the tickets say that you cannot resell them like this. Not sure on the legality of not being able to resell… And they are wanting legislation to outlow selling tickets on eBay.
Anyway, the way to fix this is simple. The tickets were purchased in a bunch… Simply require at least half the people in the bunch to enter at the same time. That is, if there eight tickets were bought together, require the people to enter in no more than two or three groups. That way if the people who bought the tickets from the scalpers do not enter all together they do not get in. Simple.