If he had spent the afternoon swinging an axe at customers in a McDonalds in New York City, he would have been released on personal recognizance - for free.
That's not how a no-bail policy works. Only arrestees who are not deemed a threat to society, and have never failed a court appearance, are released. Someone swinging an axe on the street would certainly be considered a threat.
Advantages: 1. This dumbfuck will keep talking, digging his grave deeper. 2. If someone wants revenge, he is easier to find and access. 3. Less cost for the court system. Wouldn't be funny if he was kidnapped? You know because he is his own bank.