I get that but I have also seen Pesach programs and similar events advertising (or just scheduling) minyanim and different times to cater to early risers, late risers, people who care about davening at specific zmanim and people who want to daven maariv before dinner, people who are coming back from excursions late and everything in between. Many times these minyanim need outsiders, not to mention unscheduled minyanim for participants. It works both ways. This is what makes it hard. To me since, the minyan, while a service, is very important to programs to offer so people don't nix the program, I would hope they would welcome people, even though these people are taking advantage. My strong guess is most people taking advantage would not be willing to pay the extra cost for Kosherica or for the pesach program so they are not really losing and I can't imagine anyone who is willing to pay for the program saying that they weren't because they can get minyan for free anyway. The far vast majority of people paying is for the gourmet food and Jewish entertainment.