I have paid for extra side classes, before my boy was judged as an adult, just for the extra handling experience.
Now he's in the adult classes I'm happy with the open & the 3 side classes.
We've been lucky so far and have some lovely rosettes & a medal but if you entered all the classes you were allowed to & were sucesssful, you would just end up with loads of rosettes or I suppose you could claim the money but it's only a fraction compared to the extra £3 to enter each extra class
All good fun though!