You know, the reason these public officials feel free to tromp all over the rights the Sunshine LAw gives you people is that you never bother to learn what those rights are.
The commenter is right, and many people do not know what their rights are. There is a good summary of the Pennsylvania Sunshine Act here.
The Act gives the public the right to be present at the public meetings of a large number of defined "agencies." It gives the public the right to witness deliberation, policy formulation, and decision making of those agencies. The public has the right to the advertizing and public notice of agency meetings, and must be given reasonable opportunity to comment on the business before action is taken.
The Act provides only six valid purposes for which an agency can meet in executive session, and they are listed in the article linked above.
Knowing the rights is critical. Deciding how to exercise and protect those rights is left to each individual.