The risk and reward in the battle for shoppers' $$

Inside the battle for Americans' money, big business is struggling to hold on to shoppers.

In fact, 73 percent of major brand categories dropped in a measure of loyalty that gauged if shoppers would purchase the items whether on sale or not, according to Deloitte's annual American Pantry Study of more than 354 brands across 34 product categories.

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There is evidence that interest in store brands is also fading.

About four out of 10 respondents said they view buying store branded items as a sacrifice, up 10 percentage points from the year before. The portion of people who said they were more open to store branded items also dropped by 8 percentage points to about two thirds of respondents.

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"While the majority of consumers say they are committed to sustained frugality year after year, our findings point to early signs that they may finally be responding to a belated but increasingly strong economic recovery," said Barb Renner, vice chairman, Deloitte LLP and U.S. Consumer Products leader, in a release. "It creates tremendous opportunities and risks for companies in this sector, given households' lack of commitment to national brands brought on by years of stretching dollars to the limit."

Deloitte also examined just what makes customers pull the impulse trigger. A full 89 percent cited discounted prices as a reason they bought an expected item while 63 percent said they wanted to try a new item.

To gauge Americans' buying habits, Deloitte commissioned an independent research company to poll 4,013 consumers.