Mookie Betts did a good deed a few days ago getting TJ Friedl's first MLB hit and home run ball back from a fan in the stands. He traded his own signed bat for the ball. That's a pretty good trade for the fan.
https://www.cbssports.com/mlb/news/look-mookie-betts-retrieves-first-home-run-ball-for-cincinnati-reds-rookie-tj-friedl/