There is no one who knows everything in this world but I agree with you on some non sense discussions which has no value and most of them don't know why they are getting into it because it has been already discussed many times in the same thread itself.

Receiving merits is a sign that someone is getting notified by other members of bitcointalk but it doesn't mean all others are just stupid and exists here for no reason. Everyone is trying to learn something and trying to contribute in a way they can and FYI not every great post received merit and all the posts received merits are great.