I've just finished Speaking with a EA rep over this matter on live chat, I've uploaded a copy of the chat here:-
Basically if you don't wish to view the chat yourself this is the important part of the live chat:-
Does this mean that it is ok to upload other people assists to the SIms 3 exchange service without permission, can you still report them assist for plagiarism?
We have separate department for this. But I will give you brief of this. Yes, you can use someone contents that are shared on exchanges but the rights is only within Sims. You cannot use outside without permission of the contents owner.
If someone misuse your contents, you can report it.
If you want to contact our concerned support for this terms of services, please contact our PR http://info.ea.com
I hope this clears up the problem, if it's on the exchange you can have a free reign anywhere else, then it's plagiarism.