I think you should accept their offer and be thankful you have such wonderful friends. But you can offer to buy drinks after the play if you can afford it.
News update - I fudged and told them there basically weren’t any tickets left. (I decided if I spent the whole play sitting by myself, obsessing about the finances of the whole deal, I wasn’t going to enjoy it anyway.)
So we are just going to meet up for a very late dinner after the play, hang out at their place, and then I’ll stay over and wake up overlooking the trees on Central Park West. Which is just dandy by me. 
And we can either forage for Sunday breakfast somewhere (they are never home to cook - they eat out basically all the time, so the extent of their grocery stock is usually espresso, OJ, beer, and maybe yogurt if someone’s been feeling industrious), or maybe I’ll cook.
Some people who have money is that there’s no point in having it if they can’t help out family and friends sometimes. I know you already passed on the ticket, but I think it’s within the bounds of friendship for them to treat you if there’s something special going on. After all, if the tables were turned, wouldn’t you be willing to pay so that your friend could join you in something?
Funny, but I don’;t recall you agonizing that time I offered to stand you a beer…
I’d with the crowd who says graciously accept their generosity. They are well aware of the differences between your financial situations. And I firmly believe folks oughtn’t offer if they don’t want it to be accepted.
Plus, you will get to see them for dinner before, during intermission, will be able to hook up with them more readily after … I don’t see the down side. Unless it is a play you really don’t want to see.
Of course, I’m a cheap-ass mooch!
That’s because I hate beer With the very limited exception of Belgian raspberry lambic, but then they don’t have that most places.
And for that matter, I don’t remember you offering, but howdy! Nice to see you around again.
(I’ve decided that I’m blowing off the play, if there are even any tickets left at this point, but if they insist on covering dinner they will be allowed to twist my arm. Maybe I will bring over a nice bottle of wine or something.)
How often do you think they get home cooking? By your own words, they’re both super-busy workaholics, which likely means that they don’t have the time to cook. As I recall, you’re quite a good cook. So cook them something nice.
How about inviting them round for a full Sunday lunch with your father and half-brother? A roast joint with all the trimmings. And put your half-brother to work as the waiter! After all, you’re cooking, aren’t you?
Eva Luna, I’ve been in this very same situation. I’ve felt guilty and grubby over her offer to pay a substantial portion of a trans-atlantic airline ticket. She makes three times as much as me. We’ve been friends for going on 20 years now.
We talked about it and here’s the conclusion that we came to:
Money is just a resource, just like any other resource. She and I both come to the friendship with resources, some are the same, some are different. Some resources amplify and enhance what we come to the friendship with, some resources fill in the gaps for what the other one lacks. Money has a economic value, sure, but it doesn’t have “value” in that same sense in the context of a friendship. Yes, she will pay a bigger share if that means we get to see each other or travel together (we’re in different time zones). But I contribute lots of other things besides money to the friendship. And they mean more to her than any amount of money. She is generous with her money, I am generous in other areas. It works out. Plus, she knows that if the situation were ever reversed, that I would do the same for her.
Money is a tool. That’s all.
Thanks for the compliment (the rugelach must have made quite an impression!), and I may indeed do that - they have a fabulous kitchen which is probably bigger than my whole apartment, but the stove probably never gets turned on for anything more elaborate than boiling water for tea.
Eh, I’m not sure that would go over well - Dad’s place is a tad on the cramped side for 6 people, and I just don’t see that particular combo of people going together well. (Plus I’m flying home Sunday afternoon.)
How bout this - you invite yourself over for a pre-play drink/hors d’oerves (sp?).
Then while they go to the play, you stick around and cook up a feast for you all to enjoy after the play and into the wee-hours?
This is IMHO and not GD, so please forgive me for not reading the whole thread thoroughly. I apologize if I beat a dead horse. I guess I see a moral question and an etiquette question, and they are not necessarily the same thing.
I think what you need to keep in mind is the notion of equalizing the burden rather than the dollar amount. If the pain of paying for your time together is equalized, then you are not being exploitative; you’re sharing similar pain for the pleasure of sharing time together. That is, each of you make similar sacrifices, even though the dollar amounts may not be equal, because a given amount of money has different real value to us personally depending on how much money we already have.
Another way to think of it is that for the hour you spent together for the $15 meal, the cost to your friend was an extra $15, which he could have made in five minutes at work. But your sacrifice wasn’t five minutes, it was all the time and effort to make some cookies, chock full of love. Is it unfair that you take time to bake, but your friend only has to put in a few minutes extra on the job? Hell no! When you flip the situation around to time committment & effort rather than money, the moral weight appears to shift; such an arbitrary shift of moral obligation is, IMO, a sign that you might be looking at the problem the wrong way. I think that if you are equalizing the sacrifice to spend time together, then you are behaving in an honorable manner.
As for the etiquette, I wouldn’t turn down the ticket if I wanted to go. (I was once yelled at by a European woman because I, like all Americans, was too money conscious with friends.) I think it would be nice to do something to surprise them; maybe you can find a bottle of wine from a small vineyard that is reasonably priced and likely that they’ve not tried it. It’s not hand crafted, but it is a nice surprise they can enjoy later on. But you get the idea, I’m sure.
I don’t know if I’d bring up the issue with them. Originally I was going to suggest that, but then they’re in a position where, if you are burdensome in terms of money, they either have to tell you that or lie. That would be very uncomfortable for them, I’d imagine.
I actually would have offered this already, but she is hosting a bridal shower at their place in the afternoon, so the kitchen (and she) will be tied up practically until the play starts.