Do circles of whales are created who upvote themselves as it gibe them the most incentives?

You don't need to look up to the whales for the circles who upvote each other. The ROI of upvote abuse is the same on each level.

The advantage of small scale abuse is that those guys can operate under the radar and/or tolerated by the community. The problem is if you sum up all the small scale abuse, it might amount to whale level abuse. No one looks at this problem on Steemit.

For people who know themselves also offline - is this a problem knowing the gains someone makes in steem? Envy?

This could indeed be a problem and personally, I'd prefer the income and account total to be private, but at the same time, I don't have much of an income at the moment.

I also see that the society is going to a direction of becoming more transparent. So, I don't think I have any other choice but accepting the Steemit standard.

At the end someone might start to wonder if there is a way to hide their wealth here in steem. For me it seems that is very real and I habe the feeling that whales and influential persons in the steem community operate with several accounts.

Even if you operate with multiple accounts, you need a "brand" to make an income. And once the income flows through a single account, all the transactions, hence past income, is documented and you can't hide it anymore by splitting it into different accounts.

Very good post and questions. Similar questions made me think as well in the beginning. But now, I don't care that much about it to be honest.