NEW YORK – Joelle Daddino is making it difficult for stores to make money.

Like many Americans who’ve grown accustomed to deep discounts, Daddino has become so obsessed with sales that she refuses to shop any place that isn’t having one.

During the recession, retailers had more sales to lure cash-strapped Americans into stores. Now, that strategy has backfired. It has bred a group of deal junkies that won’t shop unless they see “70 percent” signs or yellow clearance stickers. They’re a thorn in the side of most retailers because the discounts it takes to get them into stores eat away at profits. In fact, retailers’ annual profit growth was cut in half between 2006 and last year, according to a survey of 122 merchants by Retail Metrics, a research firm.