See John Siegfried and Andrew Zimbalist, “The Economics of Sports Facilities and Their Communities,” Journal of Economic Perspectives 14, no. 3 (200): 95-115
[ http://www.uwlax.edu/faculty/anderson/mi… ]

Noteworthy claims (among many):

“independent work on the economic impact of stadiums and arenas has uniformly found that there is no statistically significant positive correlation between sports facility construction and economic development…

These results stand in distinct contrast to the promotional studies that are typically done by consulting firms under the hire of teams or local chambers of commerce supporting facility development. Typically, such promotional studies project future impact and almost inevitably adopt unrealistic assumptions regarding local value added, new spending, and associated multipliers. They often use a regional input-output model that depends on outdated technical coefficients which are treated as invariant to shifts in supply and demand...

The academic work on the economic impact of sports facilities and teams does not rely upon projection. Rather, it compares the local economic performance of areas with and without stadiums, arenas, and teams, controlling for other variables that affect local economic conditions...cross-section studies, for example...found no significant difference in personal income growth from 1958 to 1987 between 36 metropolitan areas that hosted a team in one of the four premier professional sports leagues and 12 otherwise comparable areas that did not. Looking at 46 cities over the 1990–94 period...higher high school graduation rates and more spending on police are what encouraged economic growth, while the presence of a major league sports team actually put a drag on the local economy.” [103-104]

(don't recommend giving the SPD more money, certainly)

See Dennis Coates, "A Closer Look at Stadium Subsidies," The American [yeah, I know, AEI, ugh], April 29, 2008.

[ http://american.com/archive/2008/april-0… ]

Coates makes a very similar argument that Siegried and Zimablist make (@13):

“The most basic question about stadiums, arenas, and sports franchises is the extent to which they contribute to the vitality of the local economy. Supporters of publicly financed stadiums argue that the benefits are substantial, while opponents say they are small and highly concentrated among the wealthiest citizens. To buttress their case, supporters mostly use economic impact studies that predict how the local economy will be affected by the stadium, while opponents compare the economy before and after the facility is constructed. Supporters tend to imply that redistribution of economic activity from the suburbs or outlying areas of a city to the downtown is desirable, while opponents generally oppose this sort of redistribution and focus instead on job and income creation.

There is little evidence of large increases in income or employment associated with the introduction of professional sports or the construction of new stadiums.
The typical economic impact study gathers data on all aspects of spending related to a stadium, including the money spent to build it and the money spent by fans in connection with the stadium (including on tickets, at restaurants, and at hotels). The impact of this spending ripples outward into other areas of the economy through a multiplier. By linking spending to employment, the study then calculates how many jobs a stadium has created. It does not perform a cost-benefit analysis, which would address the opportunity costs of raising taxes to pay for a stadium and consider alternative uses of those funds.
Academic researchers have examined the prospective economic impact studies and found a variety of methodological errors in them, all of which raise doubts about the magnitude of the predicted spending and job increases. Other scholars use data from multiple years before and after stadium construction to measure the impact of the stadium. These ex post studies reject stadium subsidies as an effective tool for generating local economic development.

My own research…has used perhaps the most extensive data, incorporating yearly observations on per capita personal income, employment, and wages in each of the metropolitan areas that was home to a professional football, basketball, or baseball team between 1969 and the late 1990s. Our analysis tried to determine the consequences of stadium construction and franchise relocations while controlling for other circumstances in the local economy. Scholars…have taken slightly different approaches, but the results are fairly constant from one analysis to another. There is little evidence of large increases in income or employment associated with the introduction of professional sports or the construction of new stadiums.

Indeed, my work with…finds that the professional sports environment—which includes the presence of franchises in multiple sports, the arrival or departure of teams, and stadium construction—may actually reduce local incomes. For example, we found that the overall sports environment reduced per capita personal income, a finding that was new in the economic literature at the time we published it...We also found that, in many local economies, wages and employment in the retail and services sectors have dropped because of professional sports.”