Leadership can come in different forms of which the most common is the tendency to see adults and generally older ones at that as those from which it cascades downwards to which experience is something many do have.
Another way of looking at this is that any organization needs to develop and encourage those skills from its youngest members upwards giving appropriate opportunities to show it and scouting is a very good example of it from beavers and cubs upwards so you may have a situation where an older scout is in day to day charge of say a cubs section for one session who may be assisted by others.
Thus a scene like that in the picture of different sections of scouting working together as one isn't unusual and provides for practical learning opportunities first hand outside of your personal achievements and formal training on such topics as roles, health and safety and safeguarding.