In certain Nordic countries (Sweden at least, I believe), all tax data is public. By extension, everybody's income is public as well. It doesn't seem to be an issue.
Looking further, it appears that Sweden has decreased the amount of transparency by requiring that people make specific requests that notify the taxpayer of the request.
https://news.ycombinator.com/item?id=9907147
Looking further, it appears that Sweden has decreased the amount of transparency by requiring that people make specific requests that notify the taxpayer of the request.
http://www.businessinsider.com/sweden-salaries-freely-availa...
Apparently, there were issues. I'd like to see this experiment run for a longer period of time in more culturally diverse environments, though.