It's ok to upvote yourself because people here are working hard to make their upvote worth more, I am working 6 months here to make my upvote worth 0.03, why I don't help myself if I earn cents ? sometime that upvote boost my post and I get much more upvotes.

Other people are investing very bog money here, why they don't have to upvote their selfs ? it's their money !

In the other hand if the whale upvote others he will also earn from his upvote, so upvoting others or yourself is both good !