conspicuous consumption

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The acquisition or display of expensive items to attract attention to one's wealth or to suggest that one is wealthy.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A public display of acquisition of possessions with the intention of gaining social prestige; excessive consumerism in order to flaunt one's purchasing power.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun buying expensive services and products in order to flaunt your wealth