Electronics Boutique started many moons ago, in a little kiosk in the middle of the King of Prussia Mall. It originally sold small calculators and similarly tiny electronic gadgets. Over the years, the stock slowly switched over to video games and computer software. They were one of the first companies to jump on the NES system after the Atari crash in '83, and reaped the benefits when the system hit big.
Today, there are about 800 in the United States, and another 100+ carrying the 'Electronics Boutique' name worldwide. EB also owns stores under the names EBX, EB Kids, GameWorld, and Brandywine Collectibles. GameWorlds are in little plazas, which is a break from EB's normal mall mentality, as well as concentrating on pre-owned games and systems much more consistently.
EB has had some kooky policies since it first began. It's return policy up until recently (10 days, resaleable condition w/ receipt) was great if the game you bought completely sucked, as they would often (9 out of 10) give you your money back. EB also had this 'frequent buyer card' where you gave them $30, and they took a whopping 5% off your purchase. Someone in Westchester must have realized that this was a lousy thing to do to people, and cancelled it a few years ago.
Electronics Boutique is still its own entity, unlike its main competitor Babbage's, which was bankruptcy prone until bought out by Barnes and Noble in 1999. With the infusion of B&N cash, competition has become more cutthroat in the last few years.