Why thousands? There are only ~100 or so sectors. Also, who said anything about generating them on the fly? The sector data is stored in a database, so the tool would only need to be operated once per restart/wipe at the database level.
There are non-MMO examples that have been released, though. MoO, Xconq, Elite, Vega Strike (OK this one's only half complete), etc... Not sure if Trade Wars was procedurally generated.