First question.Whales put their steem power into bot and get daily dividents from that. I put 350euro into system and converted to steem dollars. I pay steem dollars for upvote which is slightly bigger than I pay, but it is taken by curation reward. whales get passive income from bot, I break even with hope that will attract other votes.
Second question. If everybody only upvote itself, there is no upvoting others and this all platform have no sense. No content, no matter how brilliant will not get upvoted more than your own vote. Of course, you and everybody will drop few votes on others but that is leftover of selfvotes. I saw few people who left comment, self-voted by 100% and for post just give 10% One comment before you, had even a bot who left same text to all newcomers with 30cents upvote from his other account. Do you think that he would waste his time curating good content when he has a money producing machine?... I see you are not the case who only selvotes, but if you feel unsure about voting bots, I was unsure about selfvoting ;)