I think it is much easier to get a Merit by honest posting than for buying it and possibly get scammed. After all, a Merit buy is not allowed and if someone remarks it, your account will be tagged red. I doubt many people will risk this, or better let's say I hope this.

Is it so difficulty to get even one single Merit right now? I think not. For sure, you have to post something useful, help people or something else and your post has to be seen and awarded by a person which has sMerits, but finally it is only one Merit. Why pay for something you can earn easily?