His latest endeavor, in conjunction with the fast-expanding Marco's Pizza chain, was a fundraiser for the Corona American and Norco Little Leagues.
"I decided a long time ago that, if I ever had the opportunity to give back, I'd do it for the community I grew up in, and the community I played in," Santiago said, while signing baseballs, gloves, bats, photos and other items for youngsters who'd waited in the long line that stretched across the plaza parking lot for more than two hours.
He engaged each young fan with meaningful conversation and posed for photos with each child, flashing his big smile. It was hard to tell which party was having the better time. And, it's probably safe to say, the only way Santiago could frown in the presence of youngsters would be to stand on his head.
He makes time for them and doesn't try and make a big deal about it, either. When he was with the White Sox, he was their 2013 nominee for the Roberto Clemente Award, as well as the Marvin Miller Man of the Year Award. Since he's been with the Angels, he's never turned down a chance to make a public appearance.
"When I was in Little League, no," Santiago said, when asked if a big league player visited his part of Newark. "But later on, when I was in the minors, [then-Yankees second baseman] Robinson Cano came through, and it had a tremendous impact."
Santiago donated his first equipment contract paycheck, and his first big league paycheck, to his Little League. And he hasn't stopped giving, either, inspired by his father's tireless dedication to youth baseball. That included maintaining fields, fixing fences, and then a day spent umpiring -- with the checks for the latter work donated back to the league.
"My father just kind of instilled in us that we're going to give back," Santiago said. "And it's something I've wanted to do."
Saturday's turnout in Corona was about twice what was expected. Free pizza and cold drinks were an attraction, but so was the presence of an American League All-Star pitcher at the neighborhood plaza, far from an everyday event.
"I knew there was going to be a bunch here, because it was a free event," Santiago said. "But it was even bigger and better than I expected."
He said he counted signing "about 750 items," which seemed pretty conservative, considering the size of the adoring throng.
Santiago's Soldiers passed out about 2,000 T-shirts donated by Marco's Pizza, and about as many Angels caps were also distributed.
Santiago arrived earlier than advertised and left for Angel Stadium for Saturday night's game a little later then scheduled. Before he left, though, he spent some quality time with what appeared to be the 10 happiest kids in south Riverside County. Those boys and girls won a drawing for the once-in-a-lifetime chance to play catch, one-on-one, with a Major League pitcher.