For me, I only response on what I usually do, what I know and what I feel about it. It's their decision not to create an account so your persuasion won't work I think. If they really want to respond to threads then they should have created an account already rather than being a guest lurking in the forum.
You're right and i also supported that, why should everyone trolling around create an account if he doesn't think of doing that the first place, this will help reduce the number of shitposters and unserios minded users that may just coincidentally jump into the forum with gabage from somewhere else, I will also like yo advise thise that creates threads to also haveba follow up onthe discussions going on there, not that you just create a thread and forget about it, i believe why it was first created is for members to contribute, then we mist also learn to be active with those kind of threads and tou must not create a thread unless you have something tangible to present.