Unbridled savagery:

Twice in recent months, authorities have raided operations where finches were kept to attack each other for onlookers who bet on which birds would survive the matches. ...

Moreover, authorities worry about public safety. "The individuals who enjoy this kind of brutality, who attend these fights should be regarded as very dangerous," [Tim Rickey, the ASPCA's director of field investigations] says. "They're the same type of people who enjoy dog fighting and rooster fighting. There may be drugs or arms, and criminal backgrounds."

"Trends like this, once they get kicked off, don't take much time to catch on."