I won't call it favouritism because merit source are made merit source to merit quality posts now the problem is what you may see as quality post won't be seen as quality post by another member or merit source.
Since there's no measure for what can be called or describe as a quality post one can't rightly say that there's favouritism in the way the merit sources are distributing merit, and they where made merit source because they see them as members who knows quality posts.
Yes some times some merit source merit post that is clearly not quality however they always have a reason for it.
The only way we can say merit source are playing favoritism card is when the forum bring out standard of a post that can be called a quality post and they go meriting outside that standard.