How Exactly are Sweet Medals Calculated in New Pokémon Snap?

Does anyone know exactly how Sweet Medals are calculated? When you give Sweet Medals out to other players they are always in multiples of 10, however checking your own Sweet Medals received will show that you can receive any value, such as 1, 2, 3, etc. It seems as though as well as the multiples of 10 you get from other players you receive an odd amount of bonus medals from somewhere. Does anyone know how this is calculated, or where the extra medals come from?