Depends on your definition of wealthy, and your location. In the UK and Europe there are a number of low cost airlines, and you can easily get flights to other European countries for under £100. Obviously it's a luxury and probably not something you could afford if you're on minimum wage and struggling to pay the rent, but easily affordable with an average income and a bit of planning.

Of course, things are different in the USA where travelling to any other country (aside from Canada or Mexico if you live near the borders) is going to cost hundreds of dollars for a flight. And I guess even leaving your state even has considerable costs in car fuel or coach/train journeys.