When more and  more people will start using bitcoin after learning about crypto currency, then in democratic counrites, the governments may start thinking about bitcoin.  So making others aware of bitcoin, motivating others to learn and trade in bitcoin, will increase bitcoin using family which can pressurize their respective governments over the issue.    But no body or institution will just give up it's authorities for the sake of convenience of others.  So without regulations the Government will never accept btc as legal currency. 
In case the government is enabled to control and tax, this currency then only the they will be legalizing it.