Since when are NRL players public servants with their salaries paid from the public purse? Why should their salaries be public knowledge? Is your salary publically available?
a) it's not difficult to determine where someone's salary lies in the age of collective bargaining agreements and the internet
For example, TrueEel makes the following:
http://www.glassdoor.com.au/Hourly-Pay/McDonald-s-Crew-Member-Hourly-Pay-E432_D_KO11,22.htm
b) NRL players (and sports figures in general) absolutely get paid from the public purse. Not by the government, but by the public who support their teams and watch their programs. They make money from interested parties, and if there is a salary cap system in place, interested parties love to know what kind of "bang for buck" they are getting out of a player, or how equitable the playing field really is!
Many American sports do not reveal actual contracts to the public, but information on deals is 'leaked' (by the head office?) so that fans can keep up with who is a bargain and who ought to be maligned. AND ALSO for the purposes of salary matching in trade agreements.
A site like this:
http://data.shamsports.com/content/pages/data/salaries/index.jsp
displays NBA salaries, and their 'soft cap' system allows for trading between clubs based on salary, and a luxury tax on big spenders which is then distributed to those who do not overspend.
I'm a huge fan of a 'soft cap' (which we have in the NRL through the 'marquee player allowance and long serving player allowance anyway) and trades AND releasing information.
It gives the general public another aspect to be excited about in following their club.
eg: we're going terribly this year, would be fantastic if we could be dreaming about trading away some veterans to a team in contention to help 'stiffen them up' while clearing cap space to offer more to other players in future years, or stockpile young talent.