I Open Carried to a blue rocks game last year without any problems. I passed by several security officers and there were police all around. Whether or not they noticed, I couldn't tell you. I can tell you that there are signs forbidding the carry of a weapon on premises. Take that as you may.
Basic Gun Safety by Jeff Cooper:
1) All guns are always loaded
2) Never let the muzzle cover anything you aren't willing to destroy
3) Keep your finger off the trigger until your sights are on the target
4) Be sure of your target and what is beyond it