1)Originally, upper class youth benefited from gap years during the 17th 18th and late 19th century. During this year, they could enjoy the vast British empire. In the 1970's, backpackers restart this tradition with continued up to today.
2)Malia Obama: internship at the US embassy in Spain
Benedict Cumberbatch: teaching english at a Tibetan Buddhist monastery
Prince Harry: building a clinic in Lisotho
3) "aristocratic" "upper class" "astronomical prices"
It is mentioned that not all students or parents can afford these very expensive gap years ("a three months excursion [...] can cost upwards of 15,000 $"). It is true that if you don't have the financial background it can be hard to go on gap year maybe even impossible...
