A showcase is typically a "friendly format", so the number of games, opponents and game times are pre-determined. Coaches freely rotate players since no one is "playing to win". You could have a roster of 14 and expect each girl to sit one inning every other game (assuming 7 inning games). Pitchers will typically pitch 2 innings/game. It is much easier to keep parents happy in this format since every player sits an equal number of innings (assuming you have a good coach whose objective is to get every girl seen as much as possible).
I have not heard of many TB teams that are "showcase only", but I guess it could happen.
I have not heard of many TB teams that are "showcase only", but I guess it could happen.