> because it tends to be dominated by younger people illicitly using their older relatives' race numbersI can't say I've seen evidence of that being a massive problem specifically, though people running under other people's names is an issue more generally.
> (events tend to restrict refunds and transfers)
That isn't just to be difficult. It can affect their insurance, there can be genuine health & safety concerns, and is often enforced by running bodies that the events associate with. Not implementing such restrictions could mean the difference between an event being able to run or not.
Transfers are also an admin faf for the organisers, even ignoring that.
> I'm pretty sure only online cheating detectives pay much attention
I would suggest that this story is a reason to reconsider how sure you are about that?
If nothing else, consider that it being important enough for someone to cheat suggests it is important enough that other people don't want their achievements to be diminished by cheaters.
There are many things in life that only matter to a minority of people, that doesn't mean it is right for someone to stomp over that something for some perverse sense of self-satisfaction. While the trollish mob bullying is going too far by a massive margin, it is not wrong for people to care when someone cheats.