It has nothing to do with atmosphere. In person, you can better evaluate the quality of punches and determine if they are really connecting. No I don't keep track. Of course, judges aren't stupid. When in the first 6 rounds you've scored 7 points to Mayweather, you know he is ahead on points.
Most judges seem to work mostly for one organization.
For example, you've worked 24 world title fights and all have been WBC title bouts. Officials are not employed like an employee is for a company. But in the case of the WBC, they forbid us to work for another sanctioning body outside of our own country. In our home country we can work for all of them. There is a public perception that some judges are biased toward fighters representing the sanctioning bodies that hire them.