These posters or people that you talk of - they just might be very young (very likely scenario) so they don't know any better just yet or they are just simply stuck at their own belief system. If they believe certain things to be true, for example, their own likings based on their preference and therefore, opinions, then no amount of reasoning or arguments is going to work. These are all dogmatic attitude and no one other than their own self will be able to resolve it but only through experience. There's literally no other way. I would just leave things at that.