If the current Atlasian Constituition is anything like the US in terms of legislative powers, the coining and issuance of currency is a responsibility of the legislative branch of government. Not some private bank.
First of all, just because the government has the Constitutional authority to do something doesn't mean it is required to. The US government, for example, did not issue its own notes until the Civil War. The men who wrote the US Constitution were perfectly happy to leave the provision of money to private issuers.
In any case, this bill wouldn't stop the Federal government from issuing currency. It would simply allow private citizens and businesses to choose alternatives if they so desired.
Ok. I see no problem with that.