> The people selling food are making and selling what is in demand.
The problem is that in highly touristic areas a big chunk of the demand comes from tourists, most of which are happy to pay for crap food as long as it's marketed to them in a way that fits their expectations about the country. The crap-selling businesses have higher margins (through cheap ingredients and unskilled labor) so it's difficult for quality local cuisine restaurants to compete with them. So even if a tourist-driven market is asking for crap, I'd argue the impoverishment of local culture is an unacceptable externality.
That would not be an externality. Which type of restaurant succeeds is internal to the economic activity of people paying for food at restaurants.
Also, what type of cuisine is crap and not is extremely subjective. If a local populace is not sufficiently motivated to make and eat a specific cuisine such that it dies out, that is sad, but just one of many compromises society makes while constantly evolving due to new parameters.
The place/tribe my parents come from is losing its amazing cuisine because it requires one stay at home parent to labor for many hours per day and years and years of experience to master. I grew up eating amazing home cooked food at all of my aunts’ and great aunt’s houses, so much so that going out to eat at a US restaurant was rare and considered a lesser alternative.
However, all of their kids obtained higher education and work, so are unable to devote anywhere close to the time my aunts and grandmas did in the kitchen. Not to mention that they like doing other things like vacationing, playing sports, going to parties, etc. All the institutional knowledge of the fresh, home cooked food is going to be gone in about 20 to 30 years, it wouldn’t success as a business and individuals have priorities other than living in the kitchen.
> That would not be an externality. Which type of restaurant succeeds is internal to the economic activity of people paying for food at restaurants.
The externality is not "which type of restaurant succeeds" but the "impoverishment of the local culture". Call it a side effect if you prefer, one of the many caused by heavy tourism (rise of housing prices, replacement of local commerce by souvenir shops, etc.) that end up pushing locals out of those areas and turning them into theme parks with no soul. Of course you are free to think that's not something worth caring about as a society.
> What type of cuisine is crap and not is extremely subjective.
There's some subjectivity involved, but in the same sense there are books that are bad by any account, there's food that is crap by any account.
> If a local populace is not sufficiently motivated to make and eat a specific cuisine such that it dies out, that is sad, but just one of many compromises society makes while constantly evolving due to new parameters.
At least here in Spain and the Mediterranean Europe in general, they do. You just have to go outside of the heavily touristic areas into the ones where actual locals live. It's true that home cooking has changed a bit in a similar fashion as you describe, but it resists in family and friend gatherings during weekends and holidays.
It's an interesting point you make about the effort involved in making a dish. I'm on a mission to eat, and mostly home cook, food from as many countries as possible. I'm at about 25% of the world's countries now after several years of gradual chipping away.
From that experience I feel that there are some food traditions which will be more durable than others and, as you suggest, this is not just a matter of tourist influence but I think capitalism/market forces are behind most of it.
Factors which I think will work against long term survival include:
-high effort: more families where both parents work for money and where the family unit is very small mean fewer opportunities for elaborate preparation. In my family we think of that type of cooking as a luxury afforded to us because we are wealthy enough to have enough free time from work to do it once in a while, but in the cultures where the food originated it was built into the schedule.
-scarce ingredients: 25% is a lot of the world's countries but I know I will never reach 100%, even if I live to 110 years old. Some countries, especially island nations, have specific local herbs and vegetables that aren't available elsewhere. Over time, the market for cultivating these will decline as it is squeezed out by cash crops for export or non-indiginous crops that grow more reliably or productively. This has happened to some regional foods in my (western) home country and while they are still available, they at risk of disappearing. Another reason for scarcity is overuse e.g. with herring overfishing and surströmming scarcity.
-banned ingredients: as food standards regulations around the world gradually harmonise to allow free trade, some ingredients will be banned. This is an ongoing global war which will carry on for decades, but it already means that some cuisines aren't available in other territories. In the longer term they could be lost from their home countries (bush meat etc.). Again surströmming features in this category and only has a temporary reprieve from the EU.
-unavailable methods: in some cases it's already a stretch to say that I'm cooking the food of a country when I'm improvising with the methods and materials. I don't have a tandoor in my back yard or a wood-fired oven for baking shakh plov; I've not really got the option of digging a hole to ferment some hákarl either. With increasingly urban populations globally, many traditional cooking methods will be unfeasible for most people.
While there are good reasons for some of these influencing factors, like food safety, others are clearly unintended side-effects. There is a strong (non-economic) case for national governments dedicating resources to conserve their cultural heritage by giving their local cuisine some protection from external pressures.
The people selling food are making and selling what is in demand. Not doing that would put them out of business. What purpose does that serve?