On a recent Saturday, when lowly San Diego played the last-place Rockies, an announced crowd of 47,370 showed up at Coors Field on a perfect late-summer evening. What’s more, by the time the Rockies complete their season with a three-game series against Milwaukee next weekend, they will have drawn more than 3 million fans, their best gate since 2001. Major League Baseball, meanwhile, took a 4% dive in attendance in 2018 and is on pace for another dip this year.