You think I'm a powerful account? I do upvote a lot of people who are either appealing Cheetah or are trying to learn to use Steemit.

With self-voting there's a few differences between the types. There's people who legitimately made and financed their accounts, they fall under one class, lets say Class A. There's people who are abusing the free delegation @steem gives out and creating giant armies of accounts only for upvoting without any investment, lets say Class B. There's also people who do a mixture of the two to make a giant botnet to publish automated copy/paste content on all accounts, and then cross-upvote them, those are Class C.

The general consensus is Class A are using their own stake, Class B lose their delegation and are rendered useless, and Class C end up getting their scammed rewards removed. It's the Class C ones that are completely demolishing the reward pool but because they're not that visible and their accounts are hard to find, most people don't realize they're there. They're the reason new people can't get accounts without waiting.

That all being said, if we use your example of an LOL comment, the Class A account may say that once in a while and upvote it. Class B and C accounts will auto-post it 100 times an hour and hide it in old posts. One LOL here and there, supported by the person's own investment (SP they bought or earned) is one thing and the 100 LOLs, also known as 'comment farming' is another.

Also, as a user you do have the right to upvote your own comments and posts. That's you using your stake as you want. It's your right and freedom, as long as you're not 'comment farming' as above. (At that point it becomes so detrimental to the entire ecosystem it must be stopped.) If anyone tells you you're not allowed to vote on your own work, they're full of shit.

Hope I answered your questions.