They are a different models so that could be sufficient excuse, I don't see much difference only the colour but at 69.99 seem very overpriced for what it is, at 49.99 the same applies. They may be trying to sell more at a price which is cheaper but still high.

If you need them just go to the old obey you can get the station,trafo and box for E$113 http://www.ebay.de/itm/Marklin-60657-S-Mobile-Station-Komplettset-Black-Line-NEUHEIT-2016-/391203521347?hash=item5b158c0343:g:wUEAAOSwPc9WyS2V

but but but ... I can get a 29000 set which has all that and a complete oval of C track with R2 curves for only Euro 10 more than that ebay offering. (When I log in it is only 128 Euro).

Also I suspect that the new connection box is cheaper because someone has redesigned the electronics to make it cheaper - it may be just that they have a new assembler for the electronics who can do it cheaper. It could still run the same software, or there may be a new set of software based on the previous software to run on a cheaper microprocessor.

Another way they could push the price down is if the connection box used a different microprocessor to other items they have then changing that to the same as used elsewhere could allow them to push suppliers for a better component price.

These are all conjecture as I haven't observed the innards of either connection box, but working in the electronics industry I am aware of various ways of moving the pricing goal posts.