You do not find it strange, that nobody has ever reported on ANY forum that they have won ANY of the bigger prizes? Remember, they are saying $200 per hour and then 1 to 3 BTC in total for the lottery every week. Nobody?
This will never be proven either way, so we are wasting our time discussing this. ^hmmmmm^
It is true that it can be manipulated, but to be honest, most Bitcoin games can be manipulated.
In the case of freebitco.in it is very difficult to proove anything.. Some time ago here on Bitcointalk was thread about winnings there. In around six months nobody show real proof of the highest winning.
As you wrote - even if someone will show tx it can be just shill account.
But winnings of around 0.04 are quite frequent.
as per my view i am using for more then 2 yrs and but i have never seen any winner to claim either and one more thing is who ever are old players whos ids are 6 digits are never won any lottery, only 7 digits and new account are winning always, but that too are mostly from the site owner itself on the top 7 numbers some time in the lower bottom of winner they can select any one , to show that they are genuine.
even the payout is also made high and the faucet claim amount has become half. Now it is really waste of time to use freebitco site.