I live in Lakeview, Chicago, about three blocks from Wrigley Field where the great Chicago Cubs play baseball. Wrigley Field is fully encompassed within our eruv borders (http://www.lakefronteruv.org), and I was wondering what issues are involved in attending a game on Shabbat, when the ticket is pre-paid. Although it is not within the spirit of Shabbat, is it halachically permissable to attend a game on Shabbat, and if not, why specifically?

"Uvdin d'chol"- actions that are not in the spirit of Shabbat- are more than just undesirable; they are halachically forbidden on Shabbat. The atmosphere at a professional ball game- the competitiveness the cheering, the booing and sometimes the disappointment and the anger (sometimes even the "great Cubs" lose)- is not compatible with the spirit of sanctity that a Jew strives for on Shabbat (see Shemirat Shabbat Kehilchata I 16 9).