You're absolutely correct it's a reasonable approach. I don't disagree. I honestly would prefer that as well. But I don't get confused when I see something outside of that. If they're used to talking politics in person, they may not normally call it US politics. Or maybe they simply weren't thinking at the time. Or maybe they just thought it'd be more popular and didn't think of the downsides.

There's plenty of entirely legitimate reasons why the name could be what it is. I don't think it's weird. Again, I'd prefer otherwise, as based on name along id assume one thing, but upon visiting and seeing another, it wouldn't cause me to stumble. Like, I feel like this post would have made more sense just commenting how many US Americans are weird like that and just default. I blame exceptionalism myself, but that's just my gut.

And to be fair, it's not like naming a community "photography" and expecting only US photography. It'd be more like calling it "healthcare" or "government" or something that is commonly talked about without the "US" designator within this country.