Requiring Tickets for Yamim Noraim
For some people the idea that a synagogue requires people to purchase tickets to attend services on the Yamim Noraim (Days of Awe) is very problematic. “How can they require a Jew to pay in order to pray in a synagogue!” That Jews were sometimes forced to support the building and maintenance of a synagogue is quite old, going back at least to Tannaitic times (see Tosefta Baba Metzia 11:12). R. Meir of Rothenberg is even quoted as saying that if only ten people (he was referring to men) live in a town then everybody is forced to help complete the minyan and if somebody wants to go away for the Yamim Noraim then the community can force them to either stay or have them hire somebody else to attend the services in their place, “שכופין אותו או לישאר או להשכיר אחר במקומו.” This obligation to support, both financially and physically, services in the synagogue was also codified in the takkanot (enactments) of numerous Jewish communities (for an example see here). While every Jew should feel obligated to support their community synagogue, or at least the synagogue in which they would like to pray for the holidays, there are surely exceptional cases. If you don’t belong to a synagogue, cannot afford either membership or tickets, and an acceptable arrangement cannot be found with a synagogue, at least in NYC I know of a number of options that are either free or charge a nominal fee. Try here and here (Conservative), here and here (Orthodox). If anyone knows of Reform or Reconstructionist services that are either free or charge a nominal fee please post them in the comments.
Responsa of Meir b. Baruch (Prague), par. 1016; Mordechai, Baba Batra, chap. 1, par. 478 Teshuvot Pesakim uMinhagim of Maharam, ed. Kahane, vol. 1, p. 53, par. 24; Beit Yosef OH 55; ShAr OH 55:21. Salo Baron, The Jewish Community, vol. III, p. 142-3, n. 3; Also see this responsum by Walter Jacob.