There are a lot of hard things about growing up. No more summer vacation (still not over that), Christmas is at least as much about buying as it is receiving, and if both you and a little kid are going for a ball at a baseball game, you give it to the little kid. Because you are no longer a little kid. You might want to be one, but you give the kid a ball. You have a job, or for some reason you have enough money to be at a game. You can buy a baseball. I know you always wanted to catch a foul ball as a kid, but think about the kid. The reflected glow of the glory you are seeking is the glory they seek at that moment. Think about how you'll feel, seeing them shriek with joy after you give them the ball.
Of course, some people don't grow up. This woman at a Houston Astros game may or may not still have summer vacations, she may or may not have to give more than she receives at Christmas, but she definitely won't give the ball to that cute little girl who clearly had dibs on it.
Let's emphasize that last point one more time: this wasn't a stray foul that a crowd of people were all going for, the ball was being thrown to the cute little girl. However, in this woman's nihilistic world, all airborne balls in baseball stadiums are fair game, regardless of the circumstances, so she 1) goes for the ball, 2) catches it at the same time as the little girl, 3) wrestles it from the little girl and 4) gleefully celebrates.
But then, 5) gets shamed on the internet for being the grinch she is.