Over the last 30 years the most inflated spending category is education and healthcare, which are arguably the least import dependent.
Similarly, in education if it was just a few prestige schools it’d be easy to believe that Harvard and Yale were hiking their base rates to exploit international students while finding credits for some of the others, but the trend is across the board even at less prestigious state schools and I’d want to see data that it’s not better explained by other factors like schools maximizing revenue from student aid.