Doesn't get how adding more ss into the game people now think our exactly worth more? Explain that concept to me?
Simple concept actually. This is still related to supply and demand. Right now, the reason they're priced higher and higher is because the demand is greater as more players reach the higher levels or more players simply wish to upgrade their gear. Unfortunately, the amount of SS won't satisfy the whole community effectively, so as a result everyone is in competition for the few SS that are already on the market
In order to fix this problem, by adding an ample amount of SS back into the market, most of the community who's upgrading their gear will have enough to be satisfied, eventually to the point that Safety Stones may not be in such high demand (i.e. due to many returning to farming after their mass spendings or testing their gear out in some way, etc.). When this event happens, the demand will be so little that the seller will resort to lowering their price if they're determined to still sell it.
I'll give a similar example. When the 65 cap came out, one new crafting drop that appeared was Evolution Blood. Due to it dropping only from certain enemies in places (and the WC Forest, Gemsis and Shiver being fairly new areas), people who got it sold it for up to 50g in the auction, more or less. As the amount of 60-65 players increased, however (with the result of the new dgns being spammed often) the amount of Evo Blood increased in the market as a result. In the very end, once the 70 cap came out, it's average price is now 5-10g in the auction. Theoretically, the same can apply to any item that becomes more commonplace in the market.
Hope that explanation helped, and sorry if it was too much to read. I'm not an economics major, so I might have some illogical fallacies in my explanation.
P.S. In my honest opinion, if the prices remain the same even after a constant huge insurgence of Safety Stones in the market, the only possible guess I have at the moment as to why it would happen is due to the stubbornness of the seller wanting more gold. It's impossible to calculate the greed factor into this, but hopefully should EE ever reach that point, I hope it will not become a serious problem.