Thanks everyone for your input! It's greatly appreciated. I've often wondered what people do when they win Bitcoins from a foreign online casino, for example, and whether they owed taxes to the country where those Bitcoins originated, in this case the foreign-owned casino.
Till now government have not declared any thing bitcoin taxes up to now, even with bitcoin casino also the casino owners will not announce the winner to public because government will not tolerate illegal activities. It depends on the country where you are living till now no one paying any taxes to the government who won the bitcoin in casino.