It takes two turns, at least, to cross the Atlantic, one way. That means a round trip takes 4 years.
Pirates can't sell some of the goods they steal, if the colonists have had a party, and what they do sell they pay taxes on. "Avast, ye lubber. I be killin and pillagin, and rapin too, but I draws the line at cheatin on me taxes."
You are confusing a privateer with a pirate.