I go with clarity, and that’s the beauty of the Oxford comma. But if an organization doesn’t use the Oxford comma, then absolutely I agree with you that being consistent about usage is best.
I like to have fun pointing out that omitting the Oxford comma can cost millions, as in this true story where a Maine dairy stood to lose $5 million due to the lack of a comma in a labor law.
My colleagues at a former job liked that example a lot.
I had to Google to find out what an Oxford comma was. Never heard of it before. And my secondary school English teachers would have been horrified at its use. Absolutely no final comma before an “and”, for example.
By the by, when I started writing books I bought myself a style guide. I bought the one published by my normal newspaper, The Guardian. Fortunately, for this forum, its reference is food related - “A comma before the final ‘and’ in lists: straightforward ones (he ate ham, eggs and chips) do not need one, but sometimes it can help the reader (he ate cereal, kippers, bacon, eggs, toast and marmalade, and tea).”
On the occasions when the issue might crop up I can generally find a way of writing it to avoid any confusion. The Guardian’s example is not a good one as it appears to suggest that he ate tea which, of course, he didnt , as he drank it. It would very easily be rewritten.
An Oxford comma never adds confusion and often avoids it.
Rewriting is goodness. Have you ever seen the book Eats, Shoots & Leaves? Perhaps you would enjoy it as much as I did.
P.S. I’m a fan of style guides, too.
@tomatotomato - I loved that book too, and was getting ready to post the link when I saw your post. I’m delighted to see that there are different versions of it geared to school aged children. I also think every teacher of English, anywhere, should have a copy of it too.
Here:
Eats, Shoots and Leaves
It would behoove me to re-read this book, or another, since I don’t remember all the rules. Shocking, I know! 
I use Oxford commas but then I still double space after every “.” too.
I’m a stickler to following the operator rules and the order of operation.
Love it. You may also enjoy this fun example about comma use generally, courtesy of the witty signs by El Arroyo tacos in Austin. You can even buy a sticker for yourself.
We’d be leery of any style manual that eschews the Oxford comma:
Yes, that’s the very example! And it’s even food-related though not restaurant-related.
Yep, it’s excellent.
It took me FOREVER to break myself of that habit.
I still double space. God I am old.
That’s our story and we’re sticking to it.
My daughter, who is 24, loves Vampire Weekend and always uses an Oxford comma.
We’ve always played “grammar games” together. I would ask her if she slept good and she’d always answer no but I slept well. That sort of thing. If someone uses an incorrect form of an adverb, we still look at each other and say LY. She’s doing graphic design work and is often called upon to review text.
I stopped in 1984 when WordPerfect (who I believe introduced the internal capital letter) automatically added space after periods, although I used a Selectric often enough for a while to have to be able to switch back and forth.
One of those that drives me nuts. If I’m asked how I am, my response is that “I’m well”, not the increasingly used “I’m good”.
I still do that while typing on forums, in Word, wherever. It’s just habit after 40+ years of typing, starting with electric typewriters and moving on to CPT 8000 Word Processors, then Macs, then PC desktops and laptops. I think the ONLY place I don’t double space after a period is on my phone.
“I’m good” has become more common than “I’m well” where I live.
