So different from Baseball where dozens of balls are used per game. Get so much as a grass stain on a ball and it's out.
Earlier this year my son and I were at a Phillies game and we had the good fortune to be in a section that was pretty close to home plate...my son had his glove and near the end of the game one of the ushers came up to me and asked if my son would like one of the game- used balls...the trick is to get close to where the umpires are exiting the field and yell "Hey, Blue!" and they'll toss the used balls to kids. So my son got one!
One of the other big differences between baseball and softball is the pitching style (overhand vs. underhand).
Baseballs are also treated with a special mud that makes it easier to grip and takes some of the shine off the balls. The mud is rubbed on by the umpires before each game. All major and minor league teams and most college teams use the mud.