Going by the boarders in Google Maps, it sure looks like the Shake Shack in is Park Slope, if just barely. And yes, while the Barclays Center is not in Park Slope, it is right across the street. Stop nitpicking about such peculiarities.
The map shows the boarder as defined by google as well as the Shake Shack. There are plenty of other restaurants next to it. I can not argue for their quality or lack of.
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