NOT BASEBALL

Check boxes (and radio buttons) are useful for turning on and off sections of commands more so than say adding a row to a matrix.  You can’t easily get at the underlying variables if you add a row or column to a matrix.

Here is an example that uses check boxes to add the command +RandomInteger[{1,6}] up to 4 times.  The first box is actually a radio box so it can’t be turned off to create a blank command error.