I'm not sure you understand the system properly, but before you go on a witch hunt, I do upvote people's replies, obviously I can't upvote every single one of them, but I upvote ones which I think bring the most amount of added value to the discussion. Obviously if i could upvote everybody I would but on steemit we have a daily upvote quota. This quota I have almost used entirely to upvote authors. It takes 1 day to recover 20% of your upvoting power. If i was to continue to vote past my daily quota, then the amount of reward i could give people would drop drastically. And, it would take several days to recover my power during which I wouldn't be able to upvote anybody. So, the best course of action is to upvote my daily quota.
Even if I am earning good money, it doesn't mean I can 'afford' to upvote everyone because that's not how the system works. If i reach my daily quota, then essentially I can't afford to keep upvoting people if I want to reward them.
RE: Just Kitty : Raising kittens from birth - The joys of being a "Crazy Cat Lady"