You don't have to 'wonder' at all... I know there are already about 50 system available, that economy does exist and that there will be a lot more available when Elite Dangerous is being released. That was not the point.
The point was that it will be a though undertaking to make the randomly generated systems an interesting experience to visit. You need a purpose to go there, and yes, in my opinion it has to be more than just a few new graphics or more of the same economy. Even if we take for example 55k systems around the starting area when ED is being released -- a relatively small number compared to what the galaxy has to offer, but already a huge area to fill with stuff --, what reward will there be for visiting the systems that are even further away?
Since we are talking about randomly generated systems, there will always be an issue with random stuff: It (mostly) feels the same. Technically it won't be possible to make every area of the galaxy a unique experience and frankly I don't expect that to be the case. But what I'd love to see is some 'mechanics' in the code of the game that fills in some good/interesting (= valuable) stuff to systems that are further away, so getting there (and returning!) makes some sort of sense. If you travel 100+ LY only to find there exists more of the already known, that could be boring after a while. But if you can find new stuff there (and the 'drop rate' of interesting goods depends on how many people are around this place = less people the further you travel away), then exploring and bringing back those things to wherever you want in the galaxy makes sense.
Well, ED isn't ready yet and it won't be after the first release. Maybe ideas like this already exist, maybe the developers already have other plans. Who knows... I certainly don't as I am only playing this game and not developing it. But with so many areas to travel to, these has to be something that makes it worth it, or leaving the initial area -- no matter of its size, 50, 500, 50k systems, whatever -- could be boring. That was the point.