I went to the majority of my DC's at Jack Murphy (now Qualcomm). I don't ever remember hearing about getting the stadium for free in exchange for cleaning it.
Right on! It'll always be The Murph in my heart. About the deal, I doubt we get it for free, but the cleaning thing is like what I quoted above. I've heard from comments from various elders that the city is pleased with the cleaning we do, and is pretty lenient in dealing with the witnesses.