Well, it shows that Milan isn't transparent in it's finances; which is illegal !!
But I think the club has to show their finances to the tax commision and other authorities that request it, so in that sense Milan should be clean, if u have any suspision about how and where the money goes.
I think it is a plus that we dont reveal how much as clubs such as Chelsea and Madrid .. clearly it shows that we usually get players at or below their price. Another thing, on the bwin sponsership; clubs dont usually state how much they get (contract is worth), basically that depends on bwin, as they could have asked to keep it confidential. Just like Emirates