Yeah, exactly. And it's for good reasons. It's not greed, actually.
If scouts, like civil servants, weren't allowed to engage in political actions even as private citizens (not using any scouting logos, not in uniform, etc) then that would undercut the movement's goals, and the mom's frustration would make total sense. But that's not the case. The problem isn't fundraising for a cause that isn't scouts, the problem is associating the movement with political causes. Like you say, which cause doesn't really matter, but IMO it's worse when the cause is very divisive.