Greetings from Hong Kong!
I'm highly allergic to shellfish. I'm allergic enough that cross-contamination is an issue: If I'm served something that has been fried on the same surface as shellfish or touched with an implement that has touched shellfish, I will have a minor allergic reaction. Shellfish is so prevalent in the southern coastal Chinese diet that I have minor shellfish reactions at about half of my lunch or evening meals, even if I try to be careful. I've learned that there are only two types of restaurants that are entirely safe: strict Buddhist vegetarian restaurants and McDonalds.
I was discussing this with my hosts at a university here in Hong Kong. One of the hosts said, "Well, we could go to that Buddhist restaurant that we took [the famous vegetarian philosopher] Peter Singer to". Sounds like a good idea to me! Another host said, "Yes, but that restaurant is so expensive! Too bad there isn't another good Buddhist restaurant around." I suggested that McDonalds would be fine, really. I didn't want to force them to spend a lot of money hosting me.
It occurred to me that they should have taken Peter Singer to McDonalds, too. Singer is as famous for his argument against luxurious spending as he is for his argument in favor of vegetarianism, and one of his favorite examples of needless luxury spending is high-priced restaurant meals. The idea is that the money you spend on a luxurious restaurant meal could be donated to charity and perhaps save the life of a child living in poverty somewhere.
So here's my thought. Suppose that the two options are (a) an expensive Buddhist restaurant, maybe $300 Hong Kong dollars per person for 10 people, $3000 Hong Kong dollars total ($400 US dollars), or (b) McDonalds for $500 HKD total ($65 US dollars). The money saved by choosing option b, if donated to an effective charity, is within the ballpark of what could be expected to save one person's life [update: or maybe about a tenth of a life; estimates vary]. On the other hand, the flesh from a steer can generate about 2000 McDonald's hamburgers, so ten people would be eating only 1/200 of a steer. Clearly one [or one tenth of a] human life is more valuable than 1/200 of a steer. Therefore, the university should have taken Peter Singer to McDonalds and donated the savings to an effective charity.
Of course, there are other costs to McDonalds (other wasteful practices, environmental damage in meat production, etc.) and possibly other benefits to eating at the Buddhist restaurant (supporting good farming practices, possibly putting the profits to good use) -- but it seems unlikely that these differences would cumulatively outweigh the central tradeoff of the unsaved human life vs. 1/200 of a steer.
If I ever have the chance to take Singer to dinner, I'd like to try this argument out on him and see what he thinks. (I wouldn't be surprised if he has already thought all of this through.)
Our own dinner decision resolved in favor of the cheap student vegetarian cafeteria nearby, which I think maybe they had been hesitating about because it didn't seem fancy enough a venue for a visiting speaker. But it was perfect for me -- a rather "utilitarian" place, I might say -- and probably where they really should have taken Singer.