The lines at Chestnut Hill's Shake Shack are still endless. (Maybe that will change if they open a Harvard Square branch, though we doubt it.) But here's a little-known secret: There's actually a good, even charitable reason to linger line for hours on end.
We hear that SS has linked up with Birthday Wishes, a Newton non-profit that provides birthday parties to kids living in local homeless shelters. A portion of the proceeds from the Boston-only Lobstah Shell concrete go toward Birthday Wishes, and Shack employees will volunteer at its parties. (Awesomely, Birthday Wishes is hosting a fundraising Cake Walk in West Roxbury on May 19; read all about how you can walk or donate to the kids right here.)
Full disclosure: We wouldn't mind having a birthday party at Shake Shack ourselves. [BW]