Economics, probably.

While there might be some who feel they should have a right to rent or buy wherever they want (free market, be damned), most people understand that it's just not going to be possible to buy a two-bedroom, 1,000 square foot condo in the Back Bay for $300,000, and that they'll have to go out to Dorchester to find a home.

For young adults on a tight budget in the city, moving to a less expensive &8212; and less fashionable &8212; neighborhood is a way to make ends meet. The hood has perks. In addition to more space for less money, we may find historic housing stock, a bohemian atmosphere, and vibrant multicultural communities. Many of us were brought up in the suburbs. Now we either can't afford to move back, or can't stomach the prospect of being so isolated and bored ever again.

Of course, the trouble is, once an area goes from being "unfashionable" to "fashionable" to "hot", those who rediscovered the neighborhood are priced out of it, as more and more people move in (it's called supply and demand).

Meaning, if you rent versus buy, you're always going to be at the mercy of your landlord.

More: Never Mind the Bullets: Upsides To Living in Low-Rent Areas - By Emily Meehan, The Wall Street Journal Online