For anyone interested in this topic, I'd highly recommend this article. While a bit old (I first read it about 10 years ago in a Land Economics class), it's a great exercise in exploring the value of building stadiums with public funds. Briefly:
"...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."
Some other really interesting stuff in here around revenue sharing between players and owners, the role of Personal Seat Licenses squeezing out the average fan, and the badge value of being a "big city". Worth a read.