The legal matter
An End-User License Agreement is a contract between the maker and the users of a software package. Many of them are broadly written and some include restrictions which are unlikely to hold up in court; nevertheless, if you've agreed to such a contract it is your responsibility to honor it to the best of your ability.
If you haven't agreed to such a contract, then its existence is irrelevant to you.
Stack Overflow is a site for programmers to help each other solve programming problems, not a place for lawyers to help programmers identify legal issues. I'm certainly not willing to provide legal advice, and I doubt you are either - so resist the urge to try interpreting a contract that you suspect might apply to someone else, and avoid using any such interpretation as a stick with which to beat folks asking programming questions.
If someone's actually asking a legal question regarding some EULA, then that's off-topic: close it as such. But if the asker hasn't brought up a EULA or other 3rd-party contract, then why should you?
See also: Should moderators enforce NDAs for software vendors?
The ethical matter
This is a much broader topic, and one which has already been addressed here: Dealing with questions of nefarious intent
The short answer is, if there is consensus that someone is explicitly looking to do something that will cause harm to others, we should probably remove that question - either via offensive-flagging, down-voting + deletion, or editing into a more benign form; no one wants to be a part of a site that helps folks hurt folks.
But if it's not explicit, if there's a reasonable interpretation of the question that doesn't involve wishing to cause harm, then... Answer it, or let others do so. Do your best to lay out the pitfalls and strongly encourage those seeking a solution to find ways to do so without harming others, but don't damn the question because someone might eventually use an answer for evil. While you can and should try to dissuade someone from doing harm with the tools available to them, someone determined to do harm will always find a way.
Full disclosure: in my youth, I spent a lot of time writing mods and editors for the games that I played; more time than I actually spent playing them. I became a much better programmer from doing so than I ever would have otherwise, and frankly I think any game publisher that would try to restrict this sort of activity on the part of its users is inadvertently doing harm to the next generation. YMMV.