It seems people do that because on two posts where I talked about the dust threshold and the dustsweeper initiative people said that it is fine with them if their upvote on a comment is lost as dust because it is the thought that counts in rewarding comments on post.
I'd rather be pragmatic and if I have low SP I would go to a post of the person that left a great comment and upvote a post that I like and leave an equally good comment. Who knows I miight even get a follower if we build enough rapport.
I am very careful with my voting power and try to be above 70% so that my vote would have value. My way of thinking is not because I am selfish with my votes but rather I want to reward good content.
I usually have Steemnow or Steemdb up so sometimes I see people that have 15 SP and upvoting me with 15% voting weight, so they won't be getting any curation rewards. They also have a habit of running their Voting power ragged with it being in the 20-30% which I was also guilty when I was starting.
When I do give them advice about voting weight and power some take it, some dont.
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