Play with eToro for a few minutes some time. It's a very well-done app. Both as a game and as a trading platform, it's a move in the right direction, and it's something worth emulating.
George Soros played a role in the collapse of the Thai Baht, during the early stages of the Asian Financial Crisis in 1997. He also personally caused the sudden drop of the British Pound in the 1992 'Black Monday,' which led Britain to leave the European ERM.
People on eToto obviously will not cause this kind of damage. But it's incorrect to say that foreign exchange / currency speculation cannot cause a currency collapse.
See here for an explanation of some of the things that bad shops do: http://nondealingdesk.blogspot.com/2006/04/non-dealing-desk-...
I've never heard of etoro, but try to understand that forex is for experts only and can only serve to wipe you out.