A growing number of SoCal businesses no longer accept cash -- a trend that business owners say can speed up lines and cut costs, but critics worry might exclude certain customers.

Earlier this year, Tender Greens announced its cashless transition. All 28 locations nationwide now only accept cards or other forms of digital payment (except for its new Boston location, where state law requires businesses to accept cash).

Tender Greens president Denyelle Bruno said many customers weren't paying in cash to begin with.

"When we made this decision, less than seven percent of our customers were paying in cash," she said.

Having to accommodate cash-paying customers can be costly. Businesses like Tender Greens have to pay someone to count out the register, to put the cash in the safe and transport it to the bank securely.

Jackson Mueller, an associate director at the Milken Institute's Center for Financial Markets, says small to medium-sized U.S. companies are paying tens of billions of dollars each year on expenses related to handling cash. For businesses that don't bring in much cash to begin with, card transaction fees are much more reasonable.

"The prices could be at a competitive advantage at this point that makes it worthwhile for a small business to go, you know what, it just doesn't make sense anymore to carry cash. Let's just switch to digital," he said.

Sweetgreen, another LA-based salad chain, has also hopped on the cashless trend. So has restaurant Yellow Fever and blow-out salon chain Drybar, headquartered in Irvine.

Some critics worry, though, that going cashless will shut some customers out.

In the Los Angeles area, 8.6 percent of people are unbanked, according to a 2015 report from the U.S Federal Deposit Insurance Commission. That's means hundreds of thousands of people don't have bank-issued debit or credit cards.

UCLA Asian American Studies Center assistant director Melany De La Cruz-Viesca says the unbanked tend to be lower-income recent immigrants who either don't want to open an account or can't afford to.

"They pay for utilities, medical services and their children's education needs all through cash," she said.

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