What I don't understand is: why don't they go to a university in Europe? I just checked for my alma mater: tuition fee is ~500 euro for 1 year. You pay about 4k in rent per year (this is probably too high an estimate). The level of education is high, and the programs are available in English.
- You've never left home for more than a month.
- There will be few (if any) Americans in a European bachelor's program.
- There is a 6 to 9 hours timezone difference with home.
- You don't have an easy time getting information compared to with American universities.
- The country will not speak English (UK aside). I know they speak english in French and German unis but your landlord probably won't, nor your health insurer.
That's a massive list of stress-inducing elements you have to take into account. For a master/PhD the situation is totally different but it's still not that easy (source: did an international master programme).