Michael, I don't see how the argument is correct. It would help me understand your point of view better if you gave me your opinion on this: If I donate enough for an effective charity to save a person's life, and I then go on to shoot dead someone else because I don't like them, is what I've done morally neutral on the whole? And if not, how is that different from the original argument? As you can see, I don't think that act and omission are the same, but does our different point of view boil down to nothing more than that? I'm really trying to understand.
Because we live in a speciesist culture, it's easy to talk about animals as if they were things that were made for our pleasure. I'd like to propose a thought experiement that replaces non-human animals with humans because I think it's a useful way to see through the specisism, the belief that humans count morally and other animals don't.
Suppose a hypothetical world in which 99% of the citizens of your country ate human slaves that were raised and killed at age 15 for the purpose of eating their flesh. Suppose citizens drank human milk from slave women who were raped every 2 years so that they could produce the maximum amount of milk, and their babies separated from them at birth so that we could drink the milk intended for their babies. (As for an analogy for eggs, maybe these hypothetical people ate some human slave new-born babies because they made for some tasty recipies.) In this hypothetical world, eating slave products is absolutely normal and socially accepted. Suppose that a tiny fraction of people were vegans -- they refrained from eating any human slave products, because they believed that it's wrong to cause suffering to slaves without a moral justification. Taking pleasure in the taste of their flesh or their milk is not a moral justification, because they don't need to eat human slave products in order to survive and be healthy.
Now let me borrow some of your arguments and apply them to this hypothetical world. I will use quotation signs but I will modify some key phrases in your speech to adapt it to the slave world.
"As far as I can tell the fact that many EAs eat human slaves and their products is surprising to some because they think 'human slaves are probably morally relevant' basically implies 'we shouldn't eat human slaves'. To my ear, this sounds about as absurd as…"
"However whether you can trade refraining from eating human slaves and their products for more effective sacrifices is largely a question of whether you choose to do so. And if not eating human slaves is not the most effective way to inconvenience yourself, then it is clear that you should choose to do so. If you eat human slave flesh now in exchange for suffering some more effective annoyance at another time, you and the world can be better off."
"Here is my own calculation of how much it costs to do the same amount of good as replacing one human slave flesh meal with one vegan meal. If you would be willing to pay this much extra to eat human slave flesh for one meal, then you should eat human slave flesh. If not, then you should abstain. For instance, if eating human slave flesh does $10 worth of harm, you should eat human slave flesh whenever you would hypothetically pay an extra $10 for the privilege."
"This gives us a price of $0.0003 with the Humane League[…]. These are not price differences that will change my meal choices very often! I think I would often be willing to pay at least a couple of extra dollars to eat human slave flesh, setting aside human slave suffering."
Of course, if they were human slaves, you wouldn't talk lightly about the suffering and death you cause them when you pay someone to raise them for food, and you wouldn't talk about "a more effective way to inconvenience yourself [than to avoid eating them]." It would be immoral. But in our speciesist culture, we are able to talk lightly about the suffering and death that we cause non-human animals. It is no less immoral. By this I'm not saying you or any other non-vegan are a bad person. It's the behavior that is wrong, the person is just a human being doing the best they can with what they have. And the specisist culture makes it particularly hard to see the behavior as wrong. It was my attempt through a human slave analogy to help you see through the specisism.
Are human slaves the same as non-human animals? They are not the same, but that's not the relevant question. The relevant question is, "do human slaves deserve the same moral consideration as non-human animals?" Animals deserve equal consideration for their interests in not suffering and continuing to live as humans do, because they are equally capable of experiencing pain as humans are and are equally interested in avoiding death. I'm sure you have many justifications for eating animals or their products just as I had until recently. This page was a valuable resource for me for seeing through those excuses I had: Eating Animals: Addressing Our Most Common Justifications
As Stijn commented before, you wouldn't think that donating enough so that someone else saved a life would justify you in killing a person you really dislike. One day we'll look at raising animals for food the way we now look at keeping slaves for labour.
I invite you to consider veganism as an opportunity to lead a happy and healthy life that's more ethical. It won't be a sacrifice for more than a tiny fraction of the rest of your life.
Disclaimer: Even though I've been almost vegan for 8 years I've only recently seen my old speciesist views for what they were and stopped all intake of animal products.
I'm going to look into CBT-I.
I don't have chronic insomnia these days, but sometimes I sleep badly for a few days in a row. A few years ago I discovered Benadryl (diphenhydramine) and it works well for me. It helps me stay asleep, and it also helps me to fall asleep up to a couple of hours earlier than my sleep time when I need to wake up earlier. It's also a boon for overnight travel.
It's non-prescription, and possible side effects don't look too bad compared to other common non-prescription drugs. I don't think it's addictive or has withdrawal effects but it's not meant as more than a short-term solution.
As Derek mentioned before, Benadryl has a big anticholinergic effect and anticholinergic drugs have been linked to dementia, but I take solace in the fact that people who have allergies are allowed to take, as per the label, up to 4 doses daily of 50mg (presumably for as long as the allergy endures), and I only need one dose of 25-50mg to sleep soundly.