[kuschku]

There’s also German, where lists are done as

a, b, c and d.

Oxford comma will get marked as mistake in an essay you write in Germany, and you’ll loose points for it.

[charlesdm]

Same for Dutch. HOWEVER: why not use it? It often just does not make sense not to use it. If a sentence can be interpreted in an ambiguous way, I personally wouldn't really care.

[kuschku]

Because if you know no one will ever use it, you also reduce ambiguity.

Then you can solve the remaining issues with using — instead.