To be fair, the letter writer didn't say that she didn't speak up. Her concern was that she wasn't asked. And I would agree, that if her date ordered a meal for himself, and never once asked, "And what are you having?" it would strike me as very strange, and pretty rude.
However, I agree there's a subtext that she expects that her date should not only have asked her, but have paid for her meal. That becomes more subtle. If he invited her with "I'd like to take you out to dinner," I'd say she is right in believing he's intending to pay, let alone ask her if she actually wants, you know, dinner. If he said, "Hey, how about we meet up at Murphy's Grill and chat for a while?" then it's more likely that he intended them to buy their own meals separately. However, it would still be rude of him to order his own food to eat in front of her without asking, "Hey, you want anything?"