Another factor -- I don't eat out because it is too expensive. But not because I couldn't afford the difference cost of 5 dollars per meal; I certainly could. But the additional utility of eating out is less than $5 -- in some cases, the utility is actually negative (that is, there are cases in which I would spend more money to make my own meal than to have to go out; I have certainly turned down free meals!) I really like having control over what I eat, and I don't like a lot of things that restaurants think I should like. I hate waiting around for food; if I must wait, I'd prefer to spend that time cooking. I do not enjoy the environment of most restaurants.
Whether or not this sort of thing is what your friends mean when they say it's too expensive, I don't know. But it's hard to believe that it is not at least part of what they mean; after all, most of us can identify a simple way to save $5 that we don't take, so we must be weighing the value of the goods and services differently. It is also worth noting that it is not uncommon for people to consider going out to eat, but find that they are not particularly motivated by any of the choices -- a clear indicator that the value of going out (in those cases) is not that they are motivated by the food served.
In American society, talking about money is a taboo. It is ok to talk about how much money someone else made when they sold their company, or how much money you would like to earn yearly if you got a raise, but in many different ways, talking about money is likely to trigger some embarrassment in the brain, and generate social discomfort. As one random example: no one dares suggest that bills should be paid according to wealth, for instance, instead people quietly assume that fair is each paying ~1/n, which of course completely fails utilitarian standards.
One more interesting thing people don't talk about, but would probably be useful to know, are money trigger action patterns. That would be a trigger action pattern that should trigger whenever you have more money than X, for varying Xs.
A trivial example is when should you stop caring about pennies, or quarters? When should you start taking cabs or Ubers everywhere? These are minor examples, but there are more interesting questions that would benefit from a money trigger action pattern.
An argument can be made for instance that one should invest in health insurance prior to cryonics, cryonics prior to painting a house and recommended charities before expensive soundsystems. But people never put numbers on those things.
When should you buy cryonics and life insurance for it? When you own $1,000? $10,000? $1,000,000? Yes of course those vary from person to person, currency to currency, environment, age group and family size. This is no reason to remain silent about them. Money is the unit of caring, but some people can care about many more things than others in virtue of having more money. Some things are worth caring about if and only if you have that many caring units to spare.
I'd like to see people talking about what one should care about after surpassing specific numeric thresholds of money, and that seems to be an extremely taboo topic. Seems that would be particularly revealing when someone who does not have a certain amount suggests a trigger action pattern and someone who does have that amount realizes that, indeed, they should purchase that thing. Some people would also calibrate better over whether they need more or less money, if they had thought about these thresholds beforehand.
Some suggested items for those who want to try numeric triggers: health insurance, cryonics, 10% donation to favorite cause, virtual assistant, personal assistant, car, house cleaner, masseuse, quitting your job, driver, boat, airplane, house, personal clinician, lawyer, body guard, etc...
...notice also that some of these are resource satisfiable, but some may not. It may always be more worth financing your anti-aging helper than your costume designer, so you'd hire the 10 millionth scientist to find out how to keep you young before considering hiring someone to design clothes specifically for you, perhaps because you don't like unique clothes. This is my feeling about boats, it feels like there are always other things that can be done with money that precede having a boat, though outside view is that a lot of people who own a lot of money buy boats.