"But when Petroskey cancels an event because he disagrees with the political stands taken by some of the attendees, that's a whole different ball game (sorry). Now he 's taking an official action on behalf of the organization that he controls, and he's politicizing that organization"
Petroskey is speaking for a "PRIVATE" institution and acting with the permission of it's board. As a private concern, it is free to select and deseletct the entities it associates with, in the same fashion a person who does not support the Dixie Chicks decides not to buy their CD
As far as celebrities, they have a right to speak their opinions like anyone else; however, "leveraged" by of their celebrity status, they have greater access to the media, than mr. regular citizen. However, Mr. regular citizen may also speak, he may also choose, within his rights not to buy their CD
's, movies, TV
shows or even their sponsors products-since that is oridinary people "leverage" their freedom of speech by choosing not to financially support with whom they disagree with.