Why do the Spacers become Traders?
One thing that could be a factor would be to have the technology lost for making the engines for the Asteroid Ships. They know how to soup them up, but they don’t know how to make them. Or they don’t know how to make the machines to make them.
The impact would be that the total number of ACC is limited. This would be why they took The Dizzy Dean and would force excess population to inhabit the various asteroids.
Smaller interstellar ships could be made, but they would top out at 0.25c.
They might feel responsible for helping support the various sleeper colonies.
They would probably also resent the Terrans for the loss of life both on quarantine duty and the Great Break Out. Even non-combatants were killed.
It might be that the Terrans need something to help manufacture the vaccine?
In any event, they have to go back to the Terran System every so often and they don’t want to. Actually, the Terrans don’t want them to either.
So they can’t make new Asteroid Ships. There are about 3000 in existence. They can maintain them indefinitely, but if lost they can not be repaired. They can make all of the Asteroid bases they want and all of the space habitats. Some people will want to stay at these locations.And others will not want to be tied down to any one system.
It takes about a year to refuel/refit an ACC ship. It would be quicker to have stations that would do the repairs.
They need to be traveling to spread genetic diversity. While there are over 25 million spacers, with a capacity of 10 thousand, they need to trading people.
It is a matter of transit time - vacationers do not want to spend 7 years each way to get somewhere. If your new job took 7 years to get to, who would want to go?You can’t be shipping something that would spoil/rot in 7 years.
Hmm, perhaps they could be traveling distilleries? Where would they grow the wood to burn?
The only thing which makes sense is either something is extremely rare or they have a pipeline running.
