About the point of traditional piracy:
The historical pirates were not only robbers and murderers. They were also rebels against a totalitarian world order that puts the governments and corporations our time to shame. Their eventual merits as murdering robbers also often came out of necessity after being marginalized by society (under threat of death, torture, slavery, starvation etc) to finding protection under a criminal system of the pirate economy, fuelled by the even more distasteful exploitation of the Africa and the Americas.

So, I think the name Pirate is very apt for the party, despite it's more dire associations.