Why a ministry has the authority to do so? What I don't like about my country, and the whole UE, is the lack of democracy. And this is a good example.
A democracy needs to have real separations of powers. The legislative body creates a law, and the judiciary, based on that law, will decide on banning or not the online gambling site.
A ministry belongs to the executive branch of the Estate. It is not up to them to decide whether something is illegal or not.