Median income in the US is around $50,000. $7-8k is a family car, most of somebody's student loan balance, the entire electronics budget for ~5 years. You want them to piss it all away on a week or two? Fuck no.

International travel is a luxury for the extremely privileged. Hell, I was pretty privileged - my parents made a total of around $110k in a low-cost-of-living city - and $3,500 for New York City was a once-in-a-lifetime treat.

Granted, there are ways to do it outside of the family, like study-abroad programs. But then in addition to the cost of the vacation you're paying full tuition to not take real classes and (if you're in a field like CS) delaying graduation by a semester or more because you're not making any progress on your major.

Analysts say current airline prices are hilariously, unsustainably low. It's only going to get far, far worse.

EDIT: I should say that vacations are important and we do take them. We drive 10-15 hours and stay at AirBnbs in other 3rd-string US cities that, while pleasant, are not high-end tourist destinations. Nashville, Lawrence, Raleigh-Durham, Cape Cod, far-flung D.C. suburbs, etc. With a Prius and more than 2 people, driving far is cheaper than flying pretty much everywhere in the continental US.