Lotteries are generally a corrupt enterprise to begin with, so the moral scales probably lean toward the side of the MIT students.
There used to be a sign on I-10 as you approached the Biloxi, Mississippi area. It was for a casino and said something like "Our slots have 98% payout!". I have no doubt as to the veracity of such a statement, because 2% of the money that flows through slot machines is more than enough to turn a profit from them.
These lotteries are obviously a different story since you can buy as many tickets as you want.