Deal with the pirate in sense of RP. Just offer him to bring a badly needed commodity to his home on the next run. There you can also test, if the pirate is simply bearing the flag of a faction as an excuse to tax or if he seriously is interested to rp the faction.
However, its indifferent what you do as long as pirate and trader interact with eachother. In most cases it provides fun for all. Thats why we're here.
