The food thing reminds me of my ex. I like food, I like to cook, I like to eat, but with him food was always an issue. There'd be comments and flat out insults, loaded words like "stuffing" or "shoving it in your face" to make you seem greedy even if it was the only meal I'd eaten that day . Pointing out there is 600 calories in the drink is not about money. She's also chosing to moan about it right when he is about to eat so he can't enjoy it, and will associate it with negativity and feeling crappy. His reaction, or rather non reaction makes it seem like he is used to it, and is trying to ride it out as chatting back will just prolong it.
He did get something that they could share, so it's not like he wasn't thinking of her. She's a bit of a hypocrite to assume he would know she can't eat it bcause of sour cream because she chose to go vegan and is still learning about it years later and making mistakes. Can't expect the person who didn't choose to be vegan to know everything and not make mistakes about the lifestyle. Man, girl was even cooking her vegan bacon in bacon fat so can't blame him for being confused.
People like her are the reason I'm so paranoid about booking that kind of cabin, especially if they allow animals. Don't come for me, I like animals, but some people are just bloody filthy and allow their animals to be as well. She's probably the type that lets their dogs lick them and jump on them before serving you food without washing their hands.