It's surprisingly easy to alienate volunteers by making small changes that - to their perception - effectively kick metaphorical sand in their faces instead of thanking them for their contributions. That doesn't mean that change is impossible or that volunteer organizations are paralyzed. It does mean that change can be slow.
You're a person who wants to see results quickly and is in a position to make them happen by training and organizing races. We're glad of that. Having different types of people helps organizations.
And be cautious of criticizing accountants. There are often good reasons for doing something a specific way that aren't necessarily obvious. I don't speak to any particular issue, but from having spent several years designing software for compliance with accounting regulations. Maybe I'm an oddball... I found that learning and implementing accounting rules came with a great deal of academic satisfaction.
It's true, patience has never been my long suit, though I'm working on it. but you're absolutely right about how difficult it is to effect change with volunteers. Not impossible, but difficult for a not-patient person to accept sometimes!
I've seen many instances in Orienteering in which certain volunteers need to let go and allow others to take over roles. It is sometimes hard to bring in new ideas, personalities and view points if the roles are always filled by the same people.
Re: accounting, FWIW, I vaguely remember hearing a few years ago that the auditors recommended a different system than what had been used. It might be worth a quick email to Robin to ask whether that change affected how teams were allocated money. [Not that that will help necessarily, but it might give you a better picture.]