I think I know what you mean. I titled my latest blog post "Stop Using Single Point Estimates" but almost immediately regretted it. The tone was too rigid and link-baity. What I really wanted to say was, "Hey, point estimates are fine, but do you realize that you may be missing an opportunity by not using range estimates?" Really I just wanted to show people a different way of thinking about something. But it can be easy to pander to the up-votes.
But mostly I stay true to myself and use my blog to educate, which is truly rewarding. My favorite post is "Roadmap for Learning Rails" because it genuinely helps people and that's a wonderful feeling.
So I think if you are blogging and start feeling like a "scammer", step back and re-examine your goals. Instead of viewing it as primarily for self-promotion or making money, view it as contributing to the community and participating in the joy of education and sharing. Also, I'm realizing that the blog posts I feel the best about aren't opinionated as much as informative and helpful.