The night before Derby, in the same stretch of The Highlands, there are two very different parties. You already know if you’re going to the elite Barnstable Brown gala, where rich and famous people do rich and famous people things, but you can still stand outside and idol worship if that’s your thing — waiting for Sammy Hagar or Katie Couric or whoever to walk in. I guess last year the NFL’s cartoonish, shirtless, beer chugger Rob Gronkowski showed up. But, anyway, a few blocks over is Sherby, a street party on Sherwood Avenue with bands, food trucks, a cash bar and much less stuffiness. Gronk, if you’re reading this, stop by Sherby this year. It’s more your scene.