In the UK, "the Bill" is "the old Bill", the police. "Kill the Bill" is a favoured chant by cross anarchists opposing the "Take-Away-You-Freedom bill (2023)", and/or wishing an early demise to the police.
my first thought was the movie. but if you think about it, they're talking about killing billing problems so I'd say that's where the name comes from. (if you check out their website).
a name that makes people go "hmm that's a bit odd" is actually a very efficient way to get people to remember it next time they need them.
