People cheat. Let's agree with that. They will police themselves without a badge. Our society relies on it. Let's agree on that.
The problem in fastpitch is there are so many players and families involved. If an individual is involved in an activity with few to no other teammates it is probably more likely to get away with fudging the rules. In a fastpitch softball team scenario it's more likely that 1 or more have some morals and integrity making it more difficult for an individual to break the rules. Most coaches are going to ask about a player's age prior to allowing them to participate. Of course a player could lie, but kids will tell on themselves. Even if a player and her family tried to pull a fast one there's a good chance one of the other players know them and will say something. If a coach allows a player to participate without following up, they are just as guilty and should re-evaluate their roll model status.
The more likely action of cheating would probably be a player (or players) not on the active roster. Injuries or no shows can force a coach to call on a temporary player to field a team. That player may or may not be on the tourney roster putting the entire weekend in jeopardy.
How about those players with sudden name changes? Coach has her on the line up card as "Suzie" but for some reason all the kids and parents are cheering for "Debbie". lol. For some reason she may only be there for a game or a day and never return. Oh, and the parents thank everyone and leave in a car with license plates from another state. Rub your chin on that one. Coach may have a copy of a birth certificate in their folder but ask the kid what are her birth parent"s name. Are you going to be the one to argue with them?
The mentioned scenario will more likely occur at a local tourney rather than a qualifier, State, or national level competition.
Kids---------girls grow up too fast. I'm not going to question their age!!!! "That girl looks like she's 16 and playing 12u". So what's your point? Are you going to approach her parents and say "Make her take that makeup off she looks too old for a 12u team"!!!!!
Remember the Boys' Little League World Series years ago with the pitcher that looked like he'd been shaving for years? Even the announcers questioned his eligibility. That kid was throwing smoke! At that level anything can happen but don't you think the Little League people did as thorough a background check as they could before allowing that young man to take the mound during a televised game?
Of course the fact he lit a cigar and drove his own sports car back to his private jet to fly back to his homeland would have you wondering if everything was actually legit. No different than the 12u girl later seen driving her own sports car to the exclusive club wearing a mini dress and standing 6' tall in heals going in to go dancing while sporting a mixed drink in her hand. I guess it's feasible. The drink had an umbrella in it........................ Might be juice.................