When basically every private person has his own crypto currency, it won't affect the state's economy, as such a crypto currency won't play any role at all and will be completely useless signs. It's not going to be used anywhere, because it won't be needed for others. Therefore, wasting time and money on it doesn't make sense. The better thing is to use what is out there already, especially if it's btc
Because, the demand for a specific crypto currency is what makes it valuable, if no one would care to buy someones crypto currency it is useless. Like any other crypto currency, if the demand for a certain digital currency is high its supply would decrease and the price would pump. But, it is not bad to have your own crypto currency, I too, would want to make one someday even if it is just for me.