> 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.
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.