I can sympathize with the traders who don't want to pay a ridiculous ransom. Sometimes it is indeed a waste of time to pay a pirate, for example, 5 million credits for a leg of a run that makes only a few hundred thousand.
In my noobish days not too long ago, I definitely did ask pirates in this situation to "destroy my ship, which is covered by insurance anyways, and I'll head off in my deluxe escape pod". I don't consider it to be OORP, but it is poor RP.
Some better alternatives are listed above. Openly calling for the House Police and Militaries not only increases the speed at which you may be destroyed and continue your day, but also provides a slight, slight chance of being rescued. Another way to go is to refuse to stop, using a setmsg such as "my apologies, sir, but my brake thrusters seem to be broken" or "I wish I could, but us pilots aren't allowed to carry more than 20 (or whatever your upper limit is for paying pirates) credits in cash". Either way, you're likely to die, but give yourself some (small) chance of escape.
I have a policy of never paying pirates (or police) who ask for more than 1 million credits (which is essentially all of them). After all, if you pay off those who are trying to RP with you, where's the thrill of being chased? The opportunity to RP a good police or pirate chase is not one that I'm likely to pass up, regardless of whether I'm smuggling in an Eagle, BW Transport, or Advanced Train.
