I think the issue is that on some forums lots of merits are given out - eg posting on Meta.
On other forums hardly any merits are given out (speculation, trading, altcoins and bitcoin discussion).
That means that if you want merits you need to post exclusively in Meta.
A potential solution is to get merit sources to "patrol" a specific forum to award good posts. That way, the distribution will be more even.
Unfortunately, I've noticed that there are some sections that get much more attention from users who have a lot of merit and who are willing to give their merit away.
If you help newbies in beginners and help your chances of being merited are much lower than if you do the same thing in technical discussion usually because those newbies will have no merit to share. As for meta, I can agree with you because most if not all of my merit was earned here.