The main reason behind rejection of Bitcoin by any government is its decentralized nature. As Bitcoin is not under anyone's control its difficult to trace any transaction carried out in Bitcoin and I think this is the reason where most of the governments are afraid of accepting Bitcoin into their financial system.Although legalizing Bitcoin payments may attract a good income to any government but risk of crimes like money laundering will be increased.
Let's face it, government don't like Bitcoin because of the fact that they cannot control it, they don't know what are they going to do for this, they are after the money that they can collect but they don't know yet how they are going to implement on it because it is decentralized, so they hate it, they want people to pay proper tax so they can corrupt more.