Yes, and that's because those certain topics have people who value it who have SP. That's just how anything goes. No one is obliged to like the other content you produce and give you the same amount of rewards. If you want to focus on the money, then keep writing on those topics you actually do get rewarded for, instead of buying votes for topics that don't get rewarded by others. It's pretty simple. If you want to keep doign the content that doesn't get as many rewards, so be it. In the world outside Steem, if someone wants to support others, they aren't obliged to support everyone. They pick and choose. So too is it on Steem, people choose the type of content to support.
I'm glad you won't use bidbots anymore. I am glad this post has provided value to you and caused you to rethink things :D
I don't expect the same people who vote on the topics they value to vote on other topics they don't value. I'm grateful that I'm even making as much as I do. I guess it's just the reason I spoke of before. I liked to try and raise the value of the quality low payout posts to give the perception of consistent quality and not be embarrassed by the marked difference in rewards. Wrong, I know, but it was not out of feeling that anyone should be obligated to upvote them.
Just wanted to clear that up. ;)