> making coffee for the rich is "valuable"
There's a lot of privilege talking about what is and is not valuable, but its worth pointing out that its only a very recent, probably very temporary, phenomena that coffee is all about rich people massively overpaying in public as an act of conspicuous consumption at Starbucks, for some decades previous McDonalds and other fast food sellers made more total money selling coffee than hipster coffee shops.
There are some market bifurcation events going on, as relates to income inequality only increasing over time. For example the number of independent bicycle shops has been dropping for decades while average revenue and profit increase... thats because the market for $2000 adult bikes is extremely high social status but also very small, leading to the inaccurate observation that "there's no money selling bikes to poor people". However, sales and revenue for poor people bikes at department stores, walmart, etc, are really pretty good, its just that you can't buy a poor person bike at a cool trendy rich hipster independent bicycle store, only from extremely uncool mass retailers. There are absolute tons and boatloads of money in selling bicycles to poor people; the money is inaccessible to the "cool kids" is the only problem.
Food deserts are a similar thing; the point of talking about food deserts is to point out the individual noticing them is a really cool person.
Perhaps a HN car analogy where nothing could be cooler on social media and more valuable than bragging about selling Tesla cars to very rich people, but you won't make even a tiny fraction as much total revenue as the incredibly uncool act of selling commuter SUVs to suburbanites.
Being cool and trendy on twitter is important, but you can make many times as much money by being very uncool. To some extent the whole meta overall topic is conspicuous consumption at its finest, along the lines of I'm rich enough and privileged enough to pretend deeply uncool (as defined on social media) market opportunities literally don't exist.