Kerb appeal

If there's any place that mixes US and UK usage, it's going to be Canada.

Kerb/curb is an exception to a more general rule that when US and UK spellings differ, the British version is longer. Compare colour/color, travelled/traveled, oestrogen/estrogen, judgement/judgment, aluminium/aluminum, aeroplane/airplane, catalogue/catalog, doughnut/donut, plough/plow.

An even rarer exception that goes the other way is fulfil/fulfill.

I don't know that plough is particularly British.      

Faulkner's "Ploughman's Folly" was published in 1943.   His farm was located in NW Ohio, and his publisher was University of Oklahoma.  

Local farm families would drive up on Sunday afternoon to see Faulkner's pitiful farm and make jest, until rationing hit, but I never heard one thing about spelling. I suspect "plough" is just old, not british

Interesting examples.   It turns out that I have always preferred the British spelling of some words, in a few cases without even realizing it was British.   In order:

• I have nothing against the "-our" suffix, but I use it only when I'm in the mood.
• I definitely write "traveled", "canceled", "controled" and a few others like it, but it's only recently that I've become aware that these are British variations.   The reason is curious:   Back when I was in elementary school, an exceptionally poor student who everyone (including me) would have said was paying no attention, I was taught a rule about doubling the final consonant:   You double that consonant when the emphasis is on the final syllable and its vowel quality is short.   Thus "canned" is doubled (because it's emphasized and short), but "caned" (because it's a long 'a').   "Traveled" and "canceled" have one 'l', even though the 'e' is short, because the syllable is unemphasized.   "Controled" has only one 'l', even though the final syllable is emphasized, because the vowel is long.   Why did I retain that rule?   I dunno, but it turns out I retained a lot of stuff like that even though I thought I wasn't listening.   I still follow that rule today, and add extra words to my spell checker to make it happy.
• I don't care one way or the other about 'æ'; and 'Å“'; I can use 'em or ignore 'em without pain.
• I have always strongly preferred "judgement" to "judgment", and I never understood why.   I never knew it was a British spelling until just now.   Maybe I've read more British writing than I realized.
• "Aluminium" isn't really a British spelling, per se; I've been given to understand that it's actually the correct name.   Back when it was first being talked about (when it was first discovered as an element, perhaps?), there was an article about it in the American press that accidentally left out the 'i', and it was never corrected; Americans have been calling it "a-LOO-min-um" ever since, but the rest of the world says "al-lyoo-MINN-ee-um".   Or anyone who doesn't has been around Americans too long, I suppose.   It's been "aluminum" here so long that very few people would claim that it's just wrong, but technically I suppose that's the case.
• I've always written "catalogue" and "doughnut", too, without ever knowing until now that they're British.   I knew that "analog", "catalog" and such have been getting more frequent, and there's nothing wrong with them, really; I'm just used to writing "-logue".
• "Plough"/"plow" are interchangeable, in my lexicon.   I can't even say which one I'm more likely to write, myself; probably depends on what I've been reading recently.
• Allow me to add that "grey" still looks better to me than "gray".   I can't say why.

deaconB, it seems publishers on each coast do stick with their own, though Brits are more strict.

This appears to show the cover of Plowman's Folly by  University of Oklahoma Press, 1943

You will find English publishers that took liberty the other way on the very same American title.

My sense is Rome will never care for Barbarians but Barbarians will sometimes revert to Rome for class.