"They screwed up is why they broke that standard! All of my guesses all boil down to "they figured it wouldn't be a big deal" so let's run with that theory."
You can run with that, but it isn't necessarily accurate.
At some point every professional has to make some decisions for their client, even if they are usually quite simple. Local press is no different.
And at least where I am (TX, USA) it is pretty standard for low-end press to run stuff w/o approval beyond the basic message. I took over a client who was having ugly print ads run in the local paper, laid out by that paper. My ads look a lot better and I handle getting them printed and up to date. And the copy is exactly what my clients want (even though I don't usually send them a proof).
But they are paying me to layout ads, and they are paying the paper to print and distribute ads. These are not the same jobs or services.
Most of the local paper's clients are tiny businesses and the printer is also setting the ad. In those situations, it is not at all unusually to get the basic info and run an ad with no proof to the client. That is just part of doing business in low-end print publications who are being paid for printing and only offer ad production as a convenience to folks who buy ads.
Maybe it is different where you are, but here you would be paying for printing. Next time have your friend layout her own ad or hire a pro. IMO, you should also tell her to pay her printing bill .