Unless you know firsthand if the ads are actually ripoffs or some other negative thing, then what you will post is merely your opinion about the ad.   It might be right, or it might be wrong.

If I were to post every single ad I have ever seen and why I would never respond to the ad, it would take hundreds of posts to do so.

Not every ad that one person thinks is bad is really bad, and there are some ads that look great that are not worth responding to.